Chris Sigurty, lead producer on StarCraft II , has told PC Gamer that the game will eventually include the ability to upload and download replays of matches to Blizzard's Battle.net service.
Currently, shoutcasters are doing great things by recording commentary over the top of replays swapped by email or file-share. Soon, they'll be able to transfer replay files over the net through a later version of Battle.net.
“Our long term intention with replays is to make them much more accessible,” says Sigurty. “Our intention with Starcraft 2 is to save them up to the network and let people download them and watch them, paying attention to the pro and platinum leagues, so they can learn.”
Even despite Starcraft II's extended development, Sigurty isn't sure the feature will make it into the game for the retail release. “It's something we're looking at in a basic form for ship, but it's still unknown whether that's going to happen or not.”
Starcraft II releases on July 27th. You should probably pre-order it.