There's a LOT of bugs in the Samsung Android experience unfortunately... That said- It's still my favorite phone ever.
#1 The 4" SAMOLED screen- not too big, not too small- and OOOO the color!
#2 Form Factor (great size ratio) & looks (love the disappearing capacitive buttons)
#3 A large keyboard. (Tried to like the G2 keyboard- no thanks) still wish for more space BETWEEN the keys on the Epic- and domed keys are usually better for speed than flat- they definitely made some odd choices - but it still works for me better than any other ANDROID keyboard...
#4 Camera software. Panorama feature alone is amazing.
#5 DLNA with my PS3 makes viewing photos on my 50" plasma a breeze! Still wish sprint didn't remove the regular corded AV out so I could use my phone as a mini laptop hooked up to any size monitor though.