Rumors are coming in that a programmer for Super Smash Bros. Brawl
has recently said on his blog that the game will be featuring destructible environments and customizable characters. The environments are said to feature terrain that will reflect damage through burning and crumbling. Whether this can be used as a weapon in the game is yet to be determined, as well as the validity of the statement on a whole.
As for customizing characters, supposedly the game will employ a new stat system that allows you to customize the play style of each character, inputting data to balance its speed, strength, etc. to the player's liking. Also, it is said that each character will have an arsenal of moves that the player may map to the character, allowing for even more customization.
While this is all a huge rumor right now, we sure hope that it turns out to be truth.
[Thanks Thousand Dragoon Link