T-Mobile sent out invitations for an event to announce the first Android based mobile phone on September 23rd.
The WSJ reports that the T-Mobile Android phone will go on sale late October.
The T-Mobile G1 is supposedly the name of the HTC made phone. As reported the G1 passed the FCC as HTC Dream a couple weeks ago.
Google just demonstrated the Android phone in the UK at the Google Developer day in London. TechRadar has a write-up and a couple photos from the presentation.

I am still mixed on the Android phone. It could be a big hit with developers and the open source community, but will it capture the mainstream consumer? Can the software be as slick and easy to use as the Apple iPhone? Will the Android market catch on as the iPhone App store did? Maybe some final beauty shots and final specifications and also pricing will help to get a clearer picture of what an Android phone actually will offer.