I feel like I should probably say something a bit more specific / definitive on this.
I'm heading off for a long trip to Asia in mid-October. My original hope had been that 2.0 would be completely done by then, but while that no longer seems realistic, it is pretty much an absolute, do-whatever-it-takes necessity that a very solid beta release be ready before I go.
So the ideal scenario as it's mapped out in my head is that Beta 1 comes out end of August / early September and then a considerably more stable Beta 2 comes out in early October, just in time for the trip. But the worst-case scenario would still have at least Beta 1 available in early October, so at the very longest you have two-and-a-half months of waiting left.
I hope that clarifies things a bit - I really do hate missing all of these release dates, but it's pretty much impossible to avoid giving them out, so I think for future products we're simply going to be ridiculously ridiculously over-generous with our time estimates; for example, the official release date estimate for the desktop version could be early 2010 or something like that. Better to surprise people with an early release than disappoint them with a late one, it seems.