We just got the announcement, iPhone OS 3.0 is coming. Set your clocks, mark your calendars. It's going down March 17th. Apparently, we'll get a sneak peak at the new OS, as well as a look at a brand new version of the SDK. Exciting stuff indeed, and we'll be there live at 10am PST (1pm EST) with the liveblog. Apple's calling this an "advance preview of what we're building," so we're not expecting anything ready to go as of the 17th, but hopefully this will allow developers to start building toward future functionality (hey, how about some push notifications?), and presumably users won't have too many months to wait after that for the real deal.