I've removed the PayPal donation link from fastr and replaced it with an AdBrite "zone," which is what they call their ads, I'm guessing because "Adbrite ad" sounds redundant. So if you want to give a donation for fastr, you have to buy an ad now.
If it works out, I'll probably remove the Google ads also. The thing I've liked about Google ads is their ability to add value to web content. I don't like ads that distract from content, but I do like ads that contribute something useful to the content.
The problem is that Google ads don't fulfill their promise consistantly. For the first day of fastr, Google was advertising spyware removal. Google uses its own search algorithms to figure out what a page is about and serve relevant ads, but that search algorithm can easily fall short. Google eventually figured out that fastr is a game, and now serves game ads mostly, but it could still be better.
AdBrite seems to be better. It doesn't wait for a computer to figure out what my site's about — it lets me describe my site. Would-be advertisers can search descriptions, find a relevant site on which to advertise within a budget, and buy ads. As a publisher, I can reject ads at my whimsy. And I will; I won't run ads on fastr that I don't expect will be of any interest to people playing the game. I don't know a lot about those people, but I know they are interested in games and flickr.
Someone already bought an ad through AdBrite, and it seems to confirm my high expectations for the service. It's a game related to flickr, TagMan. It's just like hangman, only it pulls words from tags on sites like flickr, and then points back to the sites' tag page after each round. So I think moving to AdBrite is a win-win-win. Players will get more interesting ads, advertisers will get an audience of people interested in what they're selling, and I think I'll make more money.