Why, that's this month! Engadget Mobile also has reports that both Best Buy and Radio Shack are getting the Diamond in this month -- Best Buy on the 17th and Radio Shack on Sept. 2nd.
Other questions remain. Will it have the multi-faced "Diamond" back? We'll see. Pricing? Remember that Canada's Telus is offering the Touch Diamond for $149. That's in Canadian dollars - and with a three-year contract, which is the norm up there. It's going for $349 with a two-year deal. Do your own extrapolating from there.