I suffered with the Hero for almost EIGHT months without an upgrade. There were several important issues that needed to be addressed and simply were ignored until the update was available. Hero owners were screaming for the update from January until the end of May. Many of us were told that the 2.0 update would be available soon after the Moto Droid was available in November. It wasn't. Remember: The Hero was the flagship phone when it was released. That didn't light a fire with HTC or Sprint.
Unless issues come up with the Evo, I will believe that 2.2 is available when I see it on my 4.3 inch screen. And most importantly, I will not, I WILL NOT, believe anyone who says they know when it will be released. In fact, this is the LAST thread I will look at regarding the 2.2 release.
I learned my lesson, and hopefully, everyone on this forum can learn from what happened to the Hero: It will happen when it happens and not one second sooner. Don't believe any rumors and it will serve you well.