I remember the CGI for the original blade being up to par. The effects in the sequal seemed a little to ambitious for the budget they had to work with though. I dont mind that i could tell that it was a computer animation everytime Blade leaped twenty feet in the air, or was fighting against more than two enemies, but i still noticed. I see many people are saying the effects in Blade 2 were bad, but they werent. The effects went hand and hand with the tone of the film. Now if you said that the story or execution was bad, than, i could agree with you, but the effects were noticable, but decent enough to get the point across without being raunchy.
As for Blade 3 having the best graphics, i highly doubt any movie will top the CGi use in the lord of the rings movies for a while.