Update: I got an e-mail from the Google ad team asking me to remove the first paragraph of this entry because it was encouraging people to click on ads and not likely to gain customers for advertisers. I can see their point, but was surprised at the e-mail nonetheless. It’s good to see them watching out for the benefit of their advertisers though, and I respect that.
The text ads are far more effective than traditional banner ads because the advertisements are based on page content. In other words, if the page is about cars, the advertisements will be car-related. That dramatically increases the click-through rate which means the webmaster gets more money and the user isn’t annoyed by tacky flashing banners advertising hidden cameras. Sadly, ads are not allowed on personal sites so you’ll have to find another way to get rich through blogging.