It's a lot do with your lifestyle. I used to spend 90 minutes a day on a bus and train commute and if I were still doing that I'd buy a smartphone. As it is I've actually downgraded over the years although I do draw the line at one with a black and white screen. ../../..//public/style_emoticons/default/biggrin.png
And even many subways around the world are edging towards reliable wifi access. I'll be very interested to see how the world connects up in five, ten years. Will there be wifi hotspots pretty much everywhere? Will 3G, 4G, etc. catch on? I highly doubt that the existing cell-phone networks, at least with the pricing plans in the US, will be able to do the job. They need something much cheaper, and definitely with, if not infinite data plans, at the very least much higher ones than most offer at a reasonable cost. I think another big step will be in linking people's cable/internet/home phone accounts to cellular data plans. I imagine Comcast wants in on that somehow.
Really, I think I mentioned this before, but I think the way cell networks work really needs to change. It's still, like having a highway network in which each road is owned by a private company and your route is determined by which road companies you subscribe to. Instead of having Verizon and AT&T and TMobile towers all in a given area, they should all just share those towers, each paying a fee to some central entity based on their usage. Overall that should end up being cheaper for them all, since it would mean less redundancies and they could more intelligently place multiple towers to best cover an area.
That way, no matter which company you subscribed to, you would have the same coverage, and the same speed options, the only differences would be in pricing and customer service.