I don't see what the big deal is about this phone either. Compared to my Evo:
1. the screen is smaller but nicer
2. the Samsung UI is lacking in robustness compared to HTC Sense
3. the bottom buttons not working properly? I would have not bought the phone just for that problem alone.
4. The keyboard is nice if you like actual keyboard. (Coming from 2 generations of iPhones and now an Evo I'm really used to typing on the screen.)
fyi- I ran that lagtest app that was posted and I was averaging 54FPS (peak at 60).
OMJ 3.1 Rom 2.2 Froyo.
Screen difference is a wash.. Your only talking .3 inch difference in size and holding the Epic side by side you can barely tell a difference between the two screens.. Again at .3 your not loosing much real estate... Kind of like a 40" TV with full 1080p vs a 42" TV with only 720p HD.... The difference in both size and quality are not that big a deal.
Sense UI (IMO) is hands down the best third party UI on the market.. Playing around with the Epic I really don't like the UI... and my first Android phone was the Nexus One... I loved Vanilla Android but HTC sense wasn't bad at all... Plus your at least on 2.2 with the EVO.. Not like the differences between 2.1 and 2.2 are deal breakers.
The Demo I played with at Best Buy the buttons all seemed to work just fine.
The only way I can see some one going with the Epic over the EVO is the physical keyboard.. Some people (Like my wife) want a physical keyboard and stayed away from the EVO because of the virtual touch screen keyboard. But I found the Epic to feel cheap and way to plastic... My kids have toy phones that feel more solid than the Epic.... Plus I can see (like with the Pre) that slide Keyboard wearing out... My wife went with a Blackberry because she wanted a physical keyboard and every phone with a slide out keyboard she tried or used eventually the slide function breaks in one way or another...