Almost identical to Francis, with a twist.  I make almost all my revenue from AdSense (weird, I know).  It took me a while to learn to do things in keyword research- 1) focus on high revenue per 1000 visitors stats for sellecting priority keywords by linking AdSense and Googgle Analytics, and 2) looking for the highest CPC keywords in the GoogleExternal Keyword Tool and then sorting on difficulty- oddly, in my space, a few lower-competition terms have extremely high CPC,making them prime targets for new pages onmy site andSEO efforts behind them.