Can personalised search cause feedback loops? Or, put in another way, should Google mark down Google for being Google?
Google has pages in the SERPS. It has its own help and support pages, for example, and these are the most likely to be returned in any SERPs. One of Google's webmaster pages currently does well for [search engine optimisation] in Google.co.uk. Google Directory and Google Answers pages are also returned whereas the likes of Google Finance are robots.txt excluded from the index.
I use Google a lot. An awful lot. I use Google personalised search. It makes sense that the personalised search knows that I use Google a lot ... and, um, does it then bias my results in favour of including Google pages? If I click on these Google pages in Google's own SERPs then I could again show Personalised Search that I like Google's pages.
Is this personalised search? Or is this just personalised search rewarding itself?
If Google was to apply a penalty to itself, to expect a bias towards Google and therefore weigh its own domain down then that's an advance towards other search engines with similar content pages. Yahoo's travel directory has great search engine status for tourist attractions, for example.
So should Google weigh down the other search engines then? Or has Google just found an excuse to apply a "personalised penalty" to its rivals in this case?