The beta is actually listed on battlenet now and lets you do a system scan.. Last time I visited battle net a month or 2 ago it only had the opt-in options and not the sc2 icon.

I really can't wait. I saw a gameplay video of "scrap yard?" and it looked pretty sweet. It was a space setting w\ islands of land. It would be so awesome to work for blizzard on the sc2 dev team. (aside from the death threats from rabid fans who expected the game to be out 2-3 years ago ! )