Quite a few things have happened in 7 years!
Fastclick are sort of still around, they were just bought by and swallowed up by ValueClick Media - still a great network to work with.
Similarly Tribal Fusion and Casale Media are still great networks that have been going since back then.
You might also want to take a look at Federated Media, Adconion, Technorati.
There are now, however, new networks that focus more on targeting specific countries or niches such as technology or finance.
What site are you selling ads on?
Yahoo is also restarting a publisher network...