I'm sticking with the original EVO 4g. It's a solid device, I have all the apps that I need and use, and it is a great phone too.
The one thing that really made it work for me was upgrading to a 3500 mAh battery. It's now replaced the iPod Touch as my portable media device. Can listen to music/podcasts/books, watch video, and leave bluetooth and wifi on all day without completely running down the battery.
Before the battery upgrade, I was pretty much limited to email, some web surfing, texting, and phone calls to ensure I made it through the day.
I'd love to see a similar smartphone with better energy management. It will be interesting to see what gets done on that front in the future.