It's the Android system 2.2 which has features that are not available in our current 2.1 installation... such as allowing applications to installed on the SD card and use of adobe flash.. not the flash lite we have now... wifi calling... other stuff too.. just have to wait and see what they let use.
Froyo is the 2.2 Google OS, the previous one is 2.1 or Eclair. Seems that Google loves desserts The next one is Gingerbread (2.3) and the new tablet OS 3.0 is....you guessed it Honeycomb. BTW, if you are thinking to get the myTouch 4G, it comes with Froyo, but looking forward to update to Gingerbread. After all this "sweet" talk I need a cup of water.