Wooh, according to the latest update at the Smash Bros Dojo
http://www.smashbros.com/en_us/gamemode/wi-fi/wi-fi01.html online play is confirmed for Super Smash Bros Brawl, and that's all I was waiting for to make me buy the game on day one.
I'm sure the game would be fun without it, but I don't have people over often, and I only really played Melee when I wanted to play 4 player with my friends. So, I could have waited for a price drop on Brawl if it didn't have online fighting. It's good news they've got that implemented. Hopefully that friend code stuff won't be too much of a pain in the ass...