October is looking like an Android-heavy month at Optus. As well as the Dell Streak coming out on October 1, the carrier also has an exclusive on the newly-announced HTC Aria.
Nick over at Gizmodo attended the launch for the phone in Sydney this morning, and confirms a mid-October launch for the phone, which will be available on the $49 Optus cap (and presumably those above it). No word on outright buy pricing (other than the cancel-your-contract kind), but at least it's running 2.1 (which isn't Froyo, but better than sticking with 1.6). Hit Nick's post for a glimpse at the internals.