I recently watched this video about checking your search engine ranking which explains that you might not be listed as high as you think you are because Google personalises the results and lists websites that you visit regularly higher than ones that you've not visited before. http://www.bradleyspencer.com/2009/does-your-site-rank-lower-than-you-think/ I don't think that is quite right though. From my understanding Google only does that if you are using the Web History on your Google account. Does anybody else have any experience of this?
If you are logged into your google account the results will be personalised. Make sure you log out before doing any tests.
In Opera, I am always logged in. But when I do a search using IE (I never sign in to google using IE), the search result position is the same as Opera. My Web History is disabled, so it doesn't affect me?
Side with you. I used to find all my keywords are at #2 on Google SERP while I logged in my Gmail account when doing searches.