I don't know about "garbage", but they tend to cycle back and forth. ATI has struggled lately (I'm guessing mainly due to the AMD buyout/merger), but their new stuff looks pretty good. nVidia is in trouble now on different fronts, Intel is warring with them over chipsets, and the rumors (true or not) over failures in the G92/G94 GPUs have hurt.

I'm guessing a lot of it is personal preference/fanboyism. The first serious graphics card I owned was a GeForce, but I've been ATI ever since. Of course I still play MTW, so an nVidia card is a no-go. I think it's important for both of them to be competitive, for the health of the industry. Same with Intel and AMD.