Rogers was the first to get the RIM BlackBerry Curve 8900 (aka Javelin) and it looks like T-Mobile USA may be the first carrier in the U.S. to get this updated device. According to a flyer/ad posted on TmoNews the BlackBerry Curve 8900 will be launching on 11 February. This latest generation Curve is smaller than the Bold, but has many of the same specifications.
The Curve 8900 has WiFi, Bluetooth, GPS, EDGE wireless data (sorry, no T-Mobile 3G here), 3.2 megapixel camera with auto focus and video, and 512 MHz processor. I don't see anything on the site about UMA support, but since the BlackBerry Curve I have on T-Mobile supports this and the 8900 has WiFi you can bet it is likely this model will support the UMA Hotspot @Home functionality too.
UPDATE: T-Mobile just issued the official press release for the T-Mobile Curve 8900. UMA is confirmed as well as all the other specifications we already know about.