We've heard about Project Emerald before but it's all been pretty mysterious, with no exact information about what it really is. We're now a little closer to the truth. At first everyone thought it's a new Sidekick phone, but it seems this project may be about 2 new high-end phones from HTC , both with 3.5G speed: the Desire HD and Vision (which has a front camera).
Usually, HTC uses the International names to refer to its new models, so these won't be the names that will show up in T-Mobile's stores. The 2 phones should appear under the names MyTouch HD and G1 Blaze.
Even though T-Mobile is maintaining this as secret as possible, the dates have already been leaked out, and apparently one of them should be launched on September 22nd and the other on September 29th. Considering the launch date, the phones would definitely come with Android 2.2 Froyo. Android 3.0 wouldn't make sense since it won't be announced by then, and Android 2.1 would be terribly disappointing to potential buyers.