I look for these "features" in a domain name.

1. Shorter is better.
2. COM is best.
3. Generic is better (as opposed to trademarks or brandable non-words).
4. High search traffic for keyword(s) in domain (use Google keyword tool).
5. High CPC for keyword(s) in domain (use Google keyword tool).
6. Age. Older the better. Google likes OLD domain names.