When will the new iPhone software update actually come out?

I downloaded the new iTunes and like a good casual mac fanboy I trundled through the new app store section downloading some free apps and Super Monkey Ball. But I found that the 2.0 software isn’t even out yet, this seems a little weird to me. Why would they let you download the apps when you have no way of using them?
Maybe I’m just impatient but does anyone know when it’ll land?