It's not about the salary, it's about how much you put away and how much you need to live on. I make about $80k after bonuses, not a whole lot in some places like SF or NYC, but I find that in Portland, I'm able to save 40-50% after taxes. I know that would change if I bought a house or had kids, but still.
Well, I'm hoping I'll be earning more by the time I have those things. And the reason I'm saving up right now is because I can. I rent a small studio, bought a 14 year old car etc. I'm guessing this will be the only time of my life when I can put away this much. I see many doing the opposite: getting a $1500 apartment and a new car when they get their first job.