OK, so Pikachu is a 5th gen legendary...
Now I know how you felt earlier with the Porygon Magikarp incident. Ah, well. And it's my 4th (might count as 5th?) fav.
I'm just going to put a list thing in all the things I make, now, it's for the better, really...
1: Deoxys
2: Charizard and Blaziken (tied)
3: Omanyte
4: A 5th gen legendary
Now, uh... don't really know any website mascots, apart from Celebi and Bulbasaur, although that might have just been my memory being jogged. There's this Hypno's Lullaby thing in the background, but I'm not going to go with that for some reason...
I seem to remember something with an Articuno... Articuno, maybe?
Oops. Didn't scroll down far enough :p
Sorry ShadowStriker... I'm going to guess Mudkip, because I'm unimaginative.