People with skinney fingers, like me. I'm buying one as soon as I get the cash.
..I played with this thing in a Verizon store recently. I can't even begin to tell you how much I hated it. The keypad is microscopic. You almost need one of those stylus' (like the ones that come with PDA's) to push the buttons. It's awkward and uncomfortable in the hand and the slider feature feels unbalanced and generally unreliable when placed to your ear.
Who buys these things?