According to a forum post at XDA- Developers, the new Android update to the T-Mobile G2 has Wi-Fi calling, hotspot, and ability to update Google Goggles. It is also supposed to help with "reception issues."
Update 10/13/10 - T-Mobile has issued a statement denying that the update has Wi-Fi calling and hotspots.
A photograph shows that it is an update of Android 2.2 Kernel version 2.6.32.17-g43556dc htc-kenel@ul2000-Build-149#1, Build number 1.22.531.4 CL268313 release keys.
T-Mobile started selling their first 4G smartphone, the T-Mobile G2 compatible with T-Mobile's HSPA+ network, six days ago.
The T-Mobile G2 has a 3.7-inch touchscreen, QWERTY keyboard, 800 MHz Snapdragon MSM7230 processor, 5-megapixel HD video camera, music player and 8GB microSD memory pre-installed (supporting up to 32GB). It comes loaded with Android 2.2 Froyo.
The Smasung Galaxy S smartphones did not ship with Android 2.2, and users are still waiting for an update to Android 2.2 Froyo.
T-Mobile sells the G2 for $199 with a contract. T-Mobile will be pushing out an OTA update to Froyo 2.2 for the myTouch 3G tomorrow, October 13.
T-Mobile USA's HSPA+ network currently offers theoretical peak download speeds of 21Mb/s, with plans to increase speeds to 42Mb/s in 2011. However, the G2 device has a theoretical top capability of 14.4Mb/s.