Catwoman
Release Date: July 30th, 2004

Based Upon: The popular DC Comics anti-heroine (she's not exactly a "villain"), and often-romantic interest of Batman. Selina Kyle's first appearance was Batman #1 (Spring, 1940).
Abilities: I guess she acts like a cat (9 lives, always lands on her feet, ect.)

Blade: Trinity (Blade 3)
Release Date: August, 2004
Based Upon: This is the third and final film in the 'Blade' series starring Wesley Snipes, which started with Blade in 1998 and continued in 2002 with Blade II. What most people don't know is that these movies are based upon the "Blade" vampire hunter character as published by Marvel Comics (which started in the 1970s as a supporting character in "Tomb of Dracula"). The box office of the franchise is on the rise, with Blade earning $70 million in the U.S., and Blade II earning $81.6 million.
Abilities: A vampire that does not get affected by the things that affect most vampires such as sunlight and silver bullets.

The Punisher
Release Date: Summer, 2004
Based Upon: The popular character published by Marvel Comics who first appeared in "The Amazing Spider-Man" #129 in 1974, and has appeared in several incarnations in the nearly 30 years since. This film is intended to be the first of a new franchise of 'Punisher' movies, if it is successful.
Abilities: A one-man vengeance-wreaking killing machine. An army, assassin, judge and jury all rolled up into one man (and a whole lot of guns).

Fantastic Four
Release Date: December 17th, 2004
Based Upon: The long-running comic book, Fantastic Four, published by Marvel Comics since 1961.
Abilities: Reed Richards AKA Mr. Fantastic: stretches his body 
Sue Storm AKA Invisible Girl: turns invisible and creates force fields
Johnny Storm AKA Human Torch: controls fire.
Ben Grimm AKA Thing: super-strong rock.

Batman 5

Release Date: Summer, 2005
Based Upon: The character of Batman, which has been published in a variety of comic books by DC Comics since 1939 ("Detective Comics" #27). And the other 4 Batman movies, which have all hat a different person play Batman.
Abilities: I don't think Batman has any abilities he just has cool bat gadgets

Superman

Release Date: Summer, 2005
Based Upon: The popular superhero character that appears in comics published by DC Comics. He has been adapted to television and film several times in his 60-year history, most notably in a series of films that started with Superman, starring Christopher Reeve, in 1978. This is currently expected to be the first of a trilogy of films that drastically changes key elements of the characters as previously depicted in the comic books and elsewhere.
Abilities: He's Superman what abilities doesn't he have

Daredevil 2
Release Date: TBA 2005
Based Upon: This is the sequel to the 2003 hit movie, Daredevil, which topped out at $102 million in the U.S. Both movies are, of course, based upon the long-running (since 1964) character published by Marvel Comics. Two storylines from the comics that are reportedly among the top possibilities for being the basis of this movie are 'Born Again' and Kevin Smith's 'Guardian Devil' (which was sort of a sequel to 'Born Again', in as much that Daredevil is still recuperating from the events of that storyline). My guess is that 'Born Again' will be the one, with 'Guardian Angel' perhaps adapted as 'Daredevil 3.'
Abilities: After being blinded he got superhuman sences

Elektra

Release Date: TBA 2005
Based Upon: The popular Greek assassin character published in different forms by Marvel Comics who got her start in "Daredevil" #168 in 1980. And she appeared in the Daredevil movie.
Abilities: Assassin for hire, no real super powers

Iron Man
Release Date: TBA 2005
Based Upon: The long-running Marvel Comics series and character that first appeared in 1962 in Tales of Suspense #39.
Abilities: Man made of iron.

X3: X-Men 3
Release Date: May 5th, 2006 (for now)

Based Upon: This will, of course, be the third movie based on the popular 'X-Men' comics that have been published by Marvel Comics since the early 1960s. The previous films were 2000's X-Men, which grossed $157 million in the U.S. after opening to $54.5 million (on a budget of $75 million), and X2: X-Men United, which currently has grossed $199 million in the U.S. after opening to $85.6 million (on a $110 million budget).
Abilities: Mutants with many different abilities

Spider-Man 3
Release Date: Summer, 2006 (tentative)
Based Upon: This is, of course, the third movie in the film franchise based upon the popular character of Spider-Man, as published in several different comic book series by Marvel Comics. Spider-Man was released in the U.S. in May, 2002 and grossed $403.7 million on a budget of $139 million, while Spider-Man 2 is scheduled for release in July, 2004.
Abilities: Same as Spider-Man 2 

Hulk 2
Release Date: TBA The screenwriter James Schamus revealed that he's already hard at work on the sequel
Based Upon: The character published by Marvel Comics. And the movie Hulk, which has just, came out. This movie will introduce the slightly more antogonistic "Grey Hulk" to the movie going audience, with the short list of possible villains including The Abomination and The Leader.
Abilities: When he is angry he turns into a giant green monster.

Wonder Woman
Release Date: Unknown; that will depend upon when (if) filming actually does get started. It will probably be in the summer of whatever year it's ready for.
Based Upon: The long-running and popular super heroine, as published by DC Comics.
Abilities: A golden lasso and flight, plus other stuff.

Batman vs. Superman
Release Date: Unknown; it will probably be a summer tentpole release of whatever year it's eventually slotted for.
Based Upon: This project is, of course, based upon DC Comics' two most popular characters, which they've been publishing for over 60 years (Superman since 1938, Batman since 1939). There have been several movies made over the years featuring either of them, but this will be the first feature film to feature both. It's also not a "sequel" to any pre-existing movie.
Abilities: I think you know by now if you read about the other Superman and Batman movies.

Batman: Year One
Release Date: Unknown; that will depend upon when/if filming eventually gets started
Based Upon: This movie will be based upon the story, written by Frank Miller, that originally appeared in Batman #404-407, and has since been reprinted as the Batman: Year One trade paperback.
Abilities: This is the story of young Batman just learning his abilities

Green Lantern
Release Date: Unknown; depends upon when/if filming actually does get started.
Based Upon: The long-running character as published by DC Comics (on and off) since 1940, who has taken on several forms.
Abilities: A green ring that gives him powers. The original Green Lantern's ring was magical; the latter Green Lanterns rings all came from the Guardians from the planet Oa.

Plastic Man
Release Date: Unknown; that will depend upon when production eventually gets started
Based Upon: The character of 'Plastic Man', created by Jack Cole and originally published by Quality Comics from 1941 to 1956. DC Comics picked up the character when the creator committed suicide. And started publishing 'Plastic Man' stories in 1966. In the thirty years afterwards, it was hard for DC Comics to reignite his popularity as a series, but they finally did in the late 1990s. Besides comic books, Plastic Man also starred in the ABC Saturday morning cartoon, 'The Plastic Man Comedy/Adventure Show,' which aired from 1979 to 1981.
Abilities: Stretchy

Tha Flash
Release Date: Unknown; that will depend upon when production eventually gets started on this project.
Based Upon: One of the superheroes called "The Flash" that have appeared in comic books published (off and on) by DC Comics since 1940. The character has previously been adapted as a 1990-1991 live-action CBS TV series starring John Wesley Shipp.
Abilities: Runs extremely fast

Green Arrow
Release Date: Unknown; that will depend upon when/if production eventually gets started
Based Upon: The character of Green Arrow, which has been published by DC Comics (AKA National) since 1941 (Green Arrow and his sidekick Speedy first appeared in "More Fun Comics" #73, which was the very same issue that introduced Aquaman to the world).
Abilities: Skilled archer