If you are logged into any Google property (Gmail, AdWords, AdSense, Docs, etc.) while doing a Google search, your results may be personalized, without you really knowing it.
A WebmasterWorld thread discusses just that. It is funny, because often you visit your own sites more than your competitor's site. So when you do "ego" searches, the personalized results may rank your site higher, because Google knows you visit your site more often. This leads to confusion for those who want to see how well they rank in Google.
How can you see Google search results without the personalization? Two options.
(1) Log out of Google (2) Append &pws=0 to the end of your search in the URL bar
The example I gave in the WebmasterWorld thread is http://www.google.com/search?q=keyword%20phrase&pws=0
By appending that, the results won't be personalized. Yea, it may be a pain in the neck to do this. Joost de Valk released a OpenSearch plugin you can add to Internet Explorer or Firefox to make it easier. I did something similar for Safari users. It basically adds a search option to your browser search bar, which you can easily select. Here is how it looks like in Safari, but works similarly in Firefox or Internet Explorer.
I just select the Google-P and presto, I got Google results without a personalized taste. I explain more on how to set it up for Safari at my personal blog, but if you use Firefox or Internet Explorer, you will want to see Joost de Valk.
I personally keep personalized results on, but I often need to check with personalized results off. So this toolbar comes in handy. Personalization is all over the place now. In fact, I just got my July edition of Wired and noticed I was on the front cover. Personalization at its best!
I would just like to add one more thing, a bit unrelated to this post. I placed an example of how adding &pws=0 to the URL would change the results from personalized to non-personalized results. But my example, which was a search on [keyword phrase] turned out to rank my corporate site in the first position. It was totally unintentional and I had no idea I was in the first result for a search on [keyword phrase] until after I put the example in the WebmasterWorld thread. Funny, unintentional forum spam.
Forum discussion at WebmasterWorld.