It's the dawn of a new year, so let's take a look back at one of the hottest-selling phones of the last one. A low-key launch couldn't dispel a summer of hype for the handset: Apple went for evolution when we were expecting a revolution -- even though we'd seen the same with the 3G/3GS. In the cold light of January, we can see the 4S for what it is: a refined experience that lacks a compelling reason to pay an early-upgrade fee. If you were in the planning meeting for the iPhone 6 (it's a hunch), what would you be pushing for? Built-in NFC? Would you have kept Siri under wraps until it
