Agree, the probability of leaking search query data is low but again, it cannot be ruled out completely. So it's always better to be safe than sorry.
We did publish few workarounds and tricks to prevent search engines from recording your search queries. And if you want to remain extra safe, here are some more precautions that you may keep in mind before hitting the search button:
# Be careful what you type in. Avoid putting in personal information such as your name or credit card number. If you truly want to know what's being said about you online, do a "vanity search" for your name from a different computer so it's not tied to your other searches.
# If you use e-mail or other services that require logging in, use a search engine from a different company or use a different browser to avoid data linkage. For instance, if you use Microsoft Corp.'s Hotmail, be careful when searching through the company's MSN search.
Remember that if you are on a broadband connection with a dynamic IP address, you may want to consider rebooting your modem before you type that "offensive" query which you don't want the FBI to know about.