Interesting question.. and difficult to answer. No, I don’t think you can say with any certainty the value of advertising on any site unless you know a bit more about visitor numbers, page views and so on (alexa isn’t precise or reliable enough). Also the market needs to be considered – wired.com’s readership is highly likely to be a technologically savvy bunch who are much less likely to click on adverts. Mapquest on the other hand probably has a pretty good click through rate on any adverts they display.

One thing I do think is that you’re deeply underestimating the revenue potential of the sites here. I would put wired.com as at least $100,000 per month and probably more.