tedster - 8:11 pm on Jun 21, 2010 (gmt 0)
Google's layout today is quite different from a year ago - that alone has lowered click rates for many people.
In addition, rankings are not stable in many cases. Even if you turn off personalization in every way you can manage, you can still see a different ranking at different times of day. Only the query terms reports in Webmaster Tools gives you something like the big picture.