I'm sure a lot of people have heard this but if yo just google "sprint android 2.2" you'll see a whole slew of mobile media sites with the same announcement; that sprint has said that the EVO wil be getting 2.2 in the "near future" not a lot of other details were mentioned but hopefully a timeline will be coming soon...

As work on finalizing the software is under way, Sprint expects to launch Android 2.2 in the near future.

Sorry for any confusion created when we initially made this announcement. HTC EVO 4G will receive the 2.2 update, Samsung Moment and HTC Hero will not. Future devices launching with 2.1 also will be updated to 2.2

With the Android 2.2 upgrade, customers can expect improvements to include the following benefits: updates to user interface, improved EAS Support, improved browser performance, including Flash 10x Support, voice dialing over Bluetooth and application storage on external memory.

source: HTC Evo 4G Forum