We recently went. I only gambled $15, I had a great time. Jzero is right, if you don't gamble its actually a pretty cheap place to vacation. The city is so outrageous it was fun just to walk around in. They've got foot bridges all over the place so you hardly have to cross the street. There's tons of shows, which are a bit expensive for the most part. Circe de sole? shows are pretty popular...we went and saw the one about sex. And we watched the tournament of kings show at excaliber. That was is fairly cheap and a lot of fun.
The only thing we didn't do that I wanted to do was go see the hoover dam. We only went for a few days.
I actually didn't expect to like vegas, but I really really enjoyed that trip. The people were pretty nice for the most part, although some are pretty aggressive in their sells.