According to Endgadget, HTC is ready with Cupcake upgrade to T-Mobile G1 and it is up to Google and T-Mobile to bring it into your first generation Android baskets aka G1. The upgrade got it's notoriety with a slew of upgrades and fixes announced by Android Code and also when some them like on screen keyboard popped up on a few places on the net.
The most noteble and awaited updates include video recording with the camera and the browser enhancements, an inline find function and selective copy/cut and paste. The OS is itself fixed and enhanced to bring some speed enhancements.
Also in line with the earlier article, "Andoid Based Netbook, Andbook!" and outside the scope of G1 the upgrade also supposed to provide enhanced x86 support.