I used to think that hitting a six-figure salary made you wealthy. I've since changed my mind. I think "wealthy" is a pretty subjective thing, and it depends a lot on the circumstances of a person. For example, my salary would probably be considered a pretty good salary by a lot of people. Here in Boston, I don't really feel like my paycheck goes that far. The cost of living is just too damn high. I pay more in rent than a lot of people pay for their mortgages for nice-sized homes, and I live in a tiny one bedroom apartment. Talk to people in NYC, and they'd probably consider my apartment huge. It's all relative.
I think someone would have to make $200K+ for me to consider them "wealthy" in Boston standards. I do think there are lots of people who are very "comfortable", and make a solid upper-middle class salary. But "wealthy" connotates a bit more than that to me.