The upcoming Samsung Epic 4G (Sprint's Galaxy S smartphone) competes more directly with the HTC EVO 4G, but since I picked up the Samsung Captivate (AT&T's Galaxy S smartphone) today, I thought you might like to see a side-by-side specs chart and photo face-off between the two devices.
Captivate features that are better than the EVO include the Super AMOLED display with 16M colors, 1GHz Hummingbird processor, 16GB built-in memory expandable with microSD, Bluetooth 3.0, and native 802.11n WiFi (no root required). Conversely, the EVO trumps the Captivate with its larger screen, 4G connectivity, HDMI port, front-facing camera, 8MP rear camera, built-in kickstand, and the ability to sideload apps. AT&T doesn't allow this (boo!); fortunately for Swype fans, the Captivate comes with the keyboard alternative preloaded (it also has the regular Android keyboard and a Samsung one).
So it's a mixed bag, depending on which features are most important to you.
The Captivate actually has some nice live wallpapers that I haven't seen before. I'll try to extract them (if that's possible) so you guys can load them on the EVO. Its TV-out function may sound as good as the EVO's HDMI output, but it displays everything on the phone (not just certain apps) so you can fully interact with it on a big screen. Another nicety is that the screen rotates in both landscape directions. Not a big deal, I know, but still nice.
The EVO is still a better phone, in my opinion, but the Captivate is solid and certainly the best Android phone currently available on AT&T (this statement may need to be revised after the Dell Streak is formally announced). So if your AT&T friends can't join you on Sprint with the EVO, then you may want to consider recommending the Captivate to them. Just make sure they know that the carrier removes the ability to sideload apps on all of its Android phones!