The Deadpool Bugle has posted a short clip of Deadpool from a special sneak preview of Hulk Vs. found on the Next Avengers dvd.
Deadpool has never been used in animation before now due to the violent nature of his character. The censors would never allow an assassin on a children's cartoon and they especially wouldn't allow one with the word DEAD in their name. (Deathstroke was renamed Slade for the Teen Titans animated series.
Censors are a tricky thing. A lot of shows, especially the Marvel cartoons of the 90s, are not even allowed to have characters say DEAD, DEATH or KILL in reference to what is going to happen to another character. You will hear Spider-Man say "You'll destroy him" or the Green Goblin say "I'll finish you off next" but never actually say that someone will be killed. (Peter Parker couldn't even say that his Uncle Ben died. He always found some other way to say it.)
This direct-to-dvd is a perfect venue for Deadpool as the PG-13 rating will allow him to be true to his character...and retain his name! How goofy would it be if everyone called him Wade?