An almost total mess, and no-one wanted to like it more than me.
The live action sequeces are flat emotionally, photographically, dramatically and every other way: Dante seems have done the impossible by making Brandon Frase, Jenna Elfman, Steve Martin and Joan Cusack plus various culty walkongs (Roger Corman, Mary Woronov) unfunny, unbelievable, and uninteresting.
The model, curiously, is not so much Who Killed Roger Rabbit as Rodriguez's Spy Kids movies -- but without the heart or the inspired originality and ingenuity. Instead, it's mindsplitting, unrelentingly meta, carpetbombing the audience with more movie quotes than Tarantino has in "Kill Bill." You say, "Sure, I remember that cartoon well, and it was a helluvalot better than this."
What the film needs -- particularly since it's gotta be pointed at least partially at kids -- is some kid characters, interesting ones. Instead, it just has lame Hollywood jokes, lame Las Vegas jokes, lame Paris jokes, and lame movie auteur jokes that had my seven year old son wondering when it was going to be funny. Sure, it was sometimes: if you go to the well that often, you'll find water somewhere.
The one exception to the general sloppy anarchy is a wonderful sequence with Bugs and Daffy chasing through the Louvre, into painting after painting after painting (most of them not at the Louvre, but so what). I'd love to have it on a loop, with the rest of the film surgically removed.