I thought you'd be upgrading soon, if you hadn't already done it.
2.1 was good and 2.2 is, in my opinion, more of a refinement and tweaking as opposed to a full blown overhaul type update.
Don't know if you check out any Evo forums but this one has some good stuff on it if you can get past some of the posts that sound like teenagers. Link --> HTC EVO 4G - Android Forums
With 2.2 you can have Chrome To Phone which is a neat app. You, or anyone that has access to your gmail account, can almost instantly click on a link on your, or their, PC and it shows up on your Evo. You can do the same thing with a highlighted phone number on your PC and it shows up in your dialer on your Evo.
I've read that some people had problems with the update but mine went smooth and nothing is missing. I also notice a slight speed increase in most functions, Wi-Fi is faster and overall it is just a much snappier phone. I'm finally getting the apps I want and, in a pinch, I can even make a phone call.