It really varies from person to person.
I had it for about a year then switched to comcast. My probelm is that I live twords the outskirts of my town in the country. The clearwire people told me that wouldnt be a problem when I asked about it so I tried it out. The problem is that basically you have an antenna in your house about the size of a large router, so for best results it should be in a window and on the side of your house facing wherever the nearest broadcasting tower is. For some people that is difficult because where they have their computer its not near a window or close to an exterior wall.
Now these may not be problems for you depending on how close you live to the broadcasting tower. But that would be somthing to look into. The connectivity is measured like a cell signal, with 5 lights. Personally I had 2 out of 5 lights consistantly. On good days I would get 3-4 bars of signal, but never a good 5 bars.
So my signal was pretty bad, which resulted in a fairly slow internet, and because the signal varied, it was very bad for gaming.
If you live near a clearwire broadcasting tower it may be good. I have friends that live close to a broadcasting tower and they say clearwire is good, however they dont do online gaming, so im not sure if it works well for that. I would imagine it would be better than AT&T unless you pay for the top broadcasting speed of At&t. I still dont think clearwire offers speeds comparable to cable just because its sent wirelessly. If you do not live close to a broadcasting tower, you wont get a good reliable signal and may experience pretty serious lag.