Oh, it's dead now, but give it until 2010 and this series will become huge. I just saw the trailer to the first movie, and ZOMG exciting! Alas something to look forward to before the World Cup!!
Trailer:
What's it about (the books anyway)?
Percy Jackson has ADHD and dyslexia, must be why he keeps getting kicked out of school. One summer, though, Percy and his mother are chased by a minotaur, which can't be right. Minotaurs aren't real! But, oh, yes they are. And Percy is a child of a god, you know...."mythological" Greek god. Percy seeks refuge at a summer camp for half-bloods (half-human half-god kids that is) and learns that he has been falsely accused of stealing Zeus's master bolt. Percy, along with a child of Athena by the name of Annabeth Chase, and Percy's best friend Grover Underwood, a satyr, embark on a quest to find the master bolt and find out who is framing Percy.
Well, that's the synopsis for the first book....it kind of leads into a lot foreshadowing that will shape up the rest of the series.
I've seen most of the cast and I must say two things:
1) Percy and Luke are really cute. I think the kid playing Percy is still jailbait though....let me go check. Oh yay! He's 17! Almost there!...oh my God, I've turned into Jessy/Papa Henry. ANYWAY, the actor playing Luke looks...good in the photos I've seen of him. Oh right, perhaps I should give visuals.
Logan Lerman, who will be portraying Percy Jackson. He was Christian Bale's son in "3:10 to Yuma". Onto Percy Jackson, I think looks-wise they did an amazing job, and from what I've seen on "3:10" I think Logan Lerman will definitely deliver.

And Jake Abel, who will be portraying Luke Castellan. He's an 1987'er so he's not jailbait.

But he's exactly as I imagined Luke to look like. Can't wait to see him with the scar!

2) The supporting cast of well known actors is AWESOME. Sean Bean as Zeus; Kevin McKidd (*yay*) as Poseidon; Steve Coogan as Hades (OMFG I can't wait to see this!!

); and most of all Brandon T. Jackson as Grover!! There's a lot more, a bunch of people signed on to be gods and evil beings in this movie, but these four have me bouncing around excitedly.
The young actors seem older than the characters are in the books (Percy looks about 14-16...12 is stretching it a bit, and in the first book Percy is just about to reach his 12th birthday), but I guess we can overlook that?
Oooo I hope the movie adaptations will be good.