Okeydokey:
-It was stated that most characters will be returning from melee, however it is widely beleived that Young Link, G&W and the Ice climbers will be replaced. There will be many more new characters to look foward too as well.
-From what has been released so far, adventure mode will be improved from melee, incorporating a storyline and many varied levels. Stay tuned for more info.
-It is doubtful that Smash Bro's Multiplayer will significantly change, it's carried the game along for years with little fault. So you can look foward to your classic Smash fights. But there are bound to be more special modes too. The biggest changes would be the items and new techniques characters can perform. Such as moving and shooting at the same time.
-The release date as announced on the website is December 3rd. Although I'm not sure if that is an international date or not.
-The Wii can play gamecube games, all you need is a game disc and a controlller. Also, Brawl will also be able to use gamecube controllers.
Hope this answers everything, check the first page of 'Brawl Info' for more.
Black
Name: Chris
FC: 3138-8446-5805