Google Marketing Tools is a feature that will integrate with QuickBooks once the partnership with Intuit is in full swing. Knowing this, Tony Ruscoe found a couple of pages that seem to be placeholders for some future functionality.
The strange part is the email addresses found on that placeholder (see the screenshot) -- I am thinking dani and fatmatt will probably change their addresses after all this attention. I guess they probably weren't just any random addresses either -- they have since been removed from the site.
The page also once contained some interesting source code according to Tony:
Anyway, in case you’re interested, the code – which seems to have been added to all the service login pages around 16 September 2006 – tries to create a QuickBooks.CoLocator ActiveX object before calling these pages in a window.showModalDialog popup, meaning it’s obviously only meant for use with Internet Explorer.