I got a Samsung Galaxy SIII for Christmas, after having an iPhone 3GS.
I bought it to get away from iTunes. The ability to plug into a PC and get a Windows Explorer screen and drag-and-drop files is worth it.
The larger increase in screen size over the iPhone, with only a smaller increase in overall size is good, but I don’t think I could go bigger and keep it in my pocket.
Screen is better resolution, but is much harder to see in sunlight than the iPhone.
Interface is pretty good, most things I’ve been able to work out or is virtually identical to iPhone. Except for the music player, depending on how you open it, will turn off if you open up anything else.
The LTE speeds are unbelivable.