This is what we do with rootbuzz, and it works well.

You'll want to acquaint yourself with custom segments if you take this approach too.

custom segments (from the google knowledge base):

http://support.google.com/googleanalytics/bin/answer.py?hl=e...

this blog post does a better job of explaining how to use them though imho:

http://www.searchenginepeople.com/blog/monitor-seo-projects-...