Robert_Charlton - 7:26 am on Sep 9, 2008 (gmt 0)

All of the online "competitive intelligence tools" that have purported to have this information, either for organic rankings or for PPC rankings, have been way off with regard to any site I've monitored.

Only way I know is to do samplings of rankings over a spectrum of easy and difficult phrases and the like on different kinds of pages on your site... and to pay attention to traffic and referral stats.

There's no point, IMO, monitoring rankings of thousands of phrases.