The info is mildly spoilerish, but nothing that would ruin the movie IMHO.
One interesting item that you may already know but was news to me is that Ed Norton was approached to play Dr. Bruce Banner in the Ang Lee version of the movie but declined. I think the opportunity to actually write (re-write?) the screenplay made him say yes to this one.
We already know that Doc Samson is in the movie. If you're not familiar with the comic book, Samson is a psychiatrist who was irradiated with Gamma rays and possesses super-strength. Fortunately for him the only side effect was green hair. He retained his normal personality and intelligence. At this point it's unknown whether he'll just be a regular guy in the movie, but I'm betting that's the case.
While in the comics The Abomination (played by Tim Roth) deliberately exposes himself to Gamma raditaion, in the film he is a soldier under General Ross who is mutated by a serum developed by the military. Unlike Banner, he can't transform back to human form, but he does retain his human mind and he's stronger than The Hulk.
According to director Louis Letterrier (from SHH):
"Obviously, General Ross is the villain, so he had to be in it, but the Abomination, Emil Blonsky, was who Marvel wanted to put in this chapter - the first chapter of our new saga - because he's the most famous. He's an enemy that can actually threaten the Hulk. It's very important for me that there is a danger. When Bruce Banner is Hulk, I didn’t feel in Ang Lee's 'Hulk' that there was any threat. He was invincible. So with Abomination there's actually a monster that can, you know, kill him when he's in the Hulk form."
Marvel big-dog Kevin Feige considers this movie to be "Part 1, the beginning of a whole new Hulk saga." Despite that it does build on the previous film by not including an origin story (thank goodness!) but picking up about 5 years after the previous film with Banner on the run and trying to find a cure for his condition. Apparently General Ross is after him not to destroy him, but in the hope of exploiting him for military purposes. Oh, and if that doesn't say "sequels planned" then I don't run a movie site. :-)
ILM (George Lucas' Industrial Light and Magic) is not doing the visual effects. Instead, Rhythm & Hues, the company that won an effects Oscar for its work on Babe, has taken over the CGI work. They have also done work on Superman Returns, The Chronicles of Narnia, Serenity and many other films.
As to The Hulk himself, of course he will be CGI, but there may be some combination of technologies (animatronics?) and no doubt motion capture. He is darker green, and will stay the same size throughout the entire film. (In Ang Lee's version he got bigger as he got angrier.)
Overall it won't be as serious as the first film, but it will be mythic in scope. There's the obligatory love story, but there are also huge, city-trashing fights. And don't forget that Louis Leterrier is directing, a guy whose previous directing jobs have all been action movies starring guys like Jason Statham and Jet Li.
It seems that The Incredible Hulk is suffering from a serious lack of "buzz," but I think it may end up coming out of nowhere, impressing both the fans and general audiences and end up being a big hit.
The Incredible Hulk opens on June 13, 2008.