Kojima is a friend of the creator of the Smash Bros. series. That's how they got Snake in the game.
Solid Snake and the Metal Gear franchise are incredicbly popular, so the addition of Snake may lure some Metal Gear fans over!
I would love to have
Sonic and Tails in Super Smash Bros. The dreams of many fanboys of having Mario and Sonic in the same game together would finally come true!
Also,
Mega Man and Dr. Wiley would make good additions, since Mega Man started on Nintendo anyways!
Also, please please please please include
King Dedede from the Kirby series.
Metaknight made into the game, so why not Dedede?
Go to
www.smashbros.com (the official site from Nintendo) and read a blog from the creator of the Smash Bros. games! It is very interesting!
EDIT: I just went to the website and found out that they put Pitt (Kid Icarus) in the game! I have always wanted to play Kid Icarus, and now with the Virtual Console on the Wii, I can!