Google started adopting the recommendations concept. You can already see similar pages for a search result, interesting pages and searches, customized news in Google Desktop. Now you can get recommended gadgets for your personalized homepage.
For example, if you like Gmail gadget, you might like these gadgets as well. The gadgets are determined statistically by looking at people's preferences and finding the most popular gadgets used by those who like one of them. Google shows a link that says "You might also like..." if you click on a search result in Google's directory, although this is not enabled for everyone.