engine - 11:31 am on Mar 29, 2012 (gmt 0) [edited by: engine at 11:32 am (utc) on Mar 29, 2012]
See What Going On In Your Google Account With 'Account Activity' [googleblog.blogspot.co.uk]
Today we're introducing Account Activity, a new feature in your Google Account. If you sign up, each month we'll send you a link to a password-protected report with insights into your signed-in use of Google services.
Knowing more about your own account activity also can help you take steps to protect your Google Account. For example, if you notice sign-ins from countries where you haven't been or devices you've never owned, you can change your password immediately and sign up for the extra level of security provided by 2-step verification.
This appears to be a security feature, rather than anything else.
I would have liked it to have been an option to remove data. When I say remove, I mean to remove it entirely from Google's servers.
[edited by: engine at 11:32 am (utc) on Mar 29, 2012]