Is Blizzard offering Starcraft II for digital download (i.e. something like Steam)?
via ShackNews "The digital release will come in addition to the boxed retail edition slated to hit stores."
wikipedia translates that article's snippet as: "The game will also be available for digital download from Blizzard shortly after release, if not on the release date"
Blizzard already sells all of their titles Digital Download via their store: http://us.blizzard.com/store/ when sc2 is released it'll likely be available there.
so: Yes, on release date? Maybe.
UPDATE: from official Starcraft 2 Website http://beta-us.battle.net/sc2/en/
Digital copies go on sale 07/27/2010 10:00 AM PDT
You can even download it now: