Sorry if this post is a bit wordy, but it's just that I love this phone that it's kind of hard where to start.
I recently got one of the Infuse 4Gs from AT&T. I was originally going to get an iPhone 4, but the salesclerk steered me towards this phone, since it had exactly the same features at exactly the same price as the iPhone 4 (which, btw, does NOT support "4G," while the Infuse does).
So here I am, with the Samsung phone. I haven't had any major problems with it. The best part about this phone is its speed. I did some Internet research on this phone after I got it, and discovered that it had a 1.2 GHz CPU, way faster than Apple's A4 processor. There is NO lag time when I access any part of the phone, and what also blew me away was that it had so many apps pre-installed, some of which I'd probably never use, but others which are deemed useful. I also love the Internet speed on this phone when it's on the data plan; it's so fast! I also love to just hold it in my hands; it's such a cool phone that I don't care about how big it is. I love how it's so thin and light.
My only major gripe about this phone, though, is the battery life. I would fully charge it about three times a day, only to have it run down to about half full after about 1.5 hours of nearly continuous use of the Internet and other data tasks. Another thing is the screen. It's a fingerprint magnet. But that's no big deal; if you have a polishing cloth, you can easily wipe the screen clean. Or just get a screen protector.
Overall, I'd rate this phone as a potential bestseller. This phone has really good cameras (both front and back) with very bright flash, HAS ADOBE FLASH PLAYER, and is so much faster! If there's anybody who wants a smartphone, I would totally recommend this phone.