Well, if you're planning to give all your personal info to Google (i.e., store all your emails in GMail and have them indexed by Google), think again: the first user information disclosure vuln. has been found while this is still in the Beta.
OTOH, Google looks into this, anyway. Quoting Mr. McNealy: "You've got zero privacy anyway. Get over it."
(Btw, you can fill my GMail inbox at email@example.com ... I've got 1000 MB of storage space to fill :-)