Yes, that is Link, Spawn, and Heihachi.
Namco gets hella props for this because:
A) This justifies releasing it on 3 (unequal) platforms
B) The gamecube, which would most likely have sold the least amount of copies world wide, will now sell alot more, because in addition to SCII totally kicking ass, it has LInk in it.
C) Just the idea that of doing this is rad. Why didn't anyone do this before.
D) Spawn is also cool.
E) I had more carefully thought out reasons, but I dont think it matters.
I'm hella excitied. I'm gonna get the PS2 version, and my friend is going to get the GC version. Cool, huh?
Also, there is a new character in each version, designed by Todd McFarlane. Yay!
More info can be found here