I personally think the AWP is lame, solely because of the quickswitch. With the right skills, it becomes an unstoppable killing machine! Just watch St3d on one of his killing rampages with his "run - scope/shoot - run" tactics that pick people off literally as soon as he sees them, 90% of the time, near or far.
The only tactics that I've seen have success against these AWP-gods is:
A.) Get into close range before they notice you, then run in circles around them and glock/sub 'em to death, or
B.) rush in pair with a good AK/Colt shooter, and let yourself be killed while he kills the AWPer-of-Doom.
B doesn't work well, either.