I think this is coming. There is already proof that this type of channel will be coming from Mario Kart Wii.

hopefully even voice chat

That would be great, thy might even add a new character or two, new levels would be good also.

Hope it'll be weekly downloads like Layton

I can believe new stages quicker than new characters. Still skeptical though.

i hope they will make downloadable stages songs and characters

Seemslike a perfect marketing strategy that would make a sh** load of money while fans keep begging to spend it, however it does also sound like something that could easily no happen : ( lets just hope Nintendo uses their heads.

Nintendo is really stepping up to make us Wii (Nintendo) fan/owners happy. They know what we want. These 3rd party developers do not know shit and like to screw us. At least we all know Nintendo is always there for us :)

This might actually be bad news. Not directly for SSBB, but remember Battlefield (I think that's it) in the beginning they released good games, then they went downwards and purely used downloadable for getting as much money as possible. Hopefully Iwata is smart enough to prevent that, but it might be the case for 3rd party.

I want added SSE story over characters, and that should be do-able (at least more so than char's)

 yes, I would even pay anything for characters. Mostly Isaac, Chrono, and Geno