Different SERP ranking while logged in a google account

[m98075]

So today I was checking my site'd SERP for the keyword I am targeting it for. It has been #1 in google.com for the keyword for the past 2-3 months (with steady traffic). Anyways for some reason it dropped to #22 overnight for google.com (with decreased traffic). While checking my ranking again manually entering it on google.com directly I noticed that it shows #22 when I am logged out of google accounts (blogger/gmail etc) but #1 if I am logged into my gmail account and searching for the same keyword (in google.com). I checked this multiple times with the same result. I have never read about this or come across this scenario before. Has anyone else experienced the same thing. My guess is that google keeps a track of your interests and somehow shows the sites you might be interested in higher than others??
Anyone willing to shed some light on this.

[Brawnydt]

You got it in one. It's called personalized search. You can opt out of it for your gmail account, or you can just sign out when you do your rank checking. I've made that mistake more times than I'm willing to admit. :)

[m98075]

Thanks.
That makes sense. Will do that.. Now to get the site back up to #1.

[lissie]

even when I am using the "unpersonalised" google search I am still suspicious - I use scroogle.org - a scarper you can be sure you have the real results then

[Brawnydt]

"Google Global" firefox extension is an amazingly cool little addon that will de personalize Google for you and quickly let you search other countries to see where you rank in their data centers. I use it all the time.