Thats a BROAD question. Its not about how many visitors you get , Its what they do when they get there.... I know people that get 10k a day and make pennies Just have a look at the adsense forums here on dp , You'll see TONs for threads " I have xxxxxxxx impressions and only made $3.00" To make money you need to work smart and try different things all the time, So point is , High traffic , low traffic , its all about what you do with it
Look at how long there staying, if a site has people on for 30s, you won't get alot of clicks. But if their staying an hour(rare for me) you might make a some $