maximillianos - 2:59 pm on May 19, 2010 (gmt 0)
You really don't need to analyze rankings. I stopped checking my rankings a year or two ago. Mostly because I get traffic from a half million key phrase combinations a month, but also because it fluctuated so much and didn't seem to matter in my traffic.
What you should spend your time on is analyzing your traffic, what pages are folks coming in on, what keywords are they searching for to hit those pages. Why are those pages a success and others not? What can you do to optimize the pages that are not getting much traffic... etc.
If you try to worry about rankings, you will end up going crazy and have many sleepless nights. Focus on what you can control and see in your own data and feedback from your users.