Of course, levels wouldn't work.  But character code could be sent prior to game start.  As I mentioned that might slow the process down, depends on how much coding goes into a single character, clones would be fairly simple, just a new skin and changes to existing values, but a character like Pokemon Trainer would obviously be a lot of code. 

Alternatively, the characters and even levels could already be on the disk and you're just paying to unlock them, but that would seem like a slimy money grab and I can't see Nintendo doing that.  MS maybe.

well it would be good if they did but i dont think they will

I generally dislike the thought of microtransactions, but new characters for Brawl just might make me like them.

 I feel the same way.

 Yet I keep buying the Civlization expansions...

 i think you didn't read my post.

Hmm it is an interesting idea, I would say free to download, or maybe an update that downloads it to the system but to use it you have to pay, which to me would make the most sense, so everyone can play online with each other and even play against the downloaded characters but not use them until you shell out the cash for it, or like some people and mod it where they're unlocked.

It wont happen. Trust me. Maybe in the next Brawl game, but not this one.

I saw it. But downloading stages made with the stage editor is different than getting a Nintendo made stage.  For online, the stage editor stages are fairly simple to transmit as all the content is already on the other person's Wii, it's only the order that the content is in that needs to be established. 

Having said this, Stage Editor is an absolutely AWESOME addition to SSB and I look forward to the 'Stage of the Day'.    Almost makes we wish we had Mii characters with Character Editor to give him moves. Almost, but not quite.

ya it would be very cool, but might likely wont happen.

 Everyone at least should know it's a pipe dream, but it is a cool thought, it took 700+ people to make the game what it is now and most of those people have already left to go on to other things, like in the interview on Nintendo's site it's a one time thing for this team.  But we can think up if it happened how would it work, etc.