We use Verizon wireless for our laptops. It does ok (~ 150-250 kbs vs. 28.8 kbs dialup) at home, and it does great when I take the laptop to work (closer to cell towers and civilization in general). But, depending on the time of day, the speed will vary. That's because phone calls, texting, wireless internet, etc., are all going through the same pipe.
Computer technology is kind of like encyclopedias. Obsolete as soon as you buy it.
I hear that they're improving and upgrading infrastructure all the time. But I believe that we're going to hit a capacity wall one of these days.
Maybe there will be some kind of breakthrough. Who knows?
Anyways, I'm sure these companies are looking at bandwidth limits because that's cheaper than adding new capacity. And, with exceedance of limits (my plan limit is 5 gig/month d/l) at $0.25/mb, it ensures them profit, too.