People... A little word on google and the advertising model it employs.
Because I buy its advertising and I also display its advertising, I get a nice $US cheque every month for doing so.
Google never ceases to amaze me with their very intelligent use of content.
Here's are some links to how google has gone from a University project to a billion dollar company that Microsoft and Yahoo now want a piece of.
From Google
https://www.google.com/adsense/overview
An example of a site that I display Google Adsense Ads on and believe me, the advertising revenue more than covers the cost of running the site:
http://eoddata.com
Another one on which a friend makes thousands of $US a month
http://knoppix.net
Its content based advertising, google - in its usual spidering - caches the pages and their key words and once you paste the generic code into your site, the advertising just adjusts to suit.
There's not a single human in sight to read the page and see if it is "worthy". NOR WILL THERE BE WITH GMAIL.
The Google servers will simply take an index of the words used and display essentially adsense ads next to your hotmail.
So your friend tells you they have the flu and voila.. there's a clarityne ad where you'd normally have other advertising on Hotmail for example. Ummm... sorry but I like the sound of that, makes for much more interesting content on the page rather than Hotmail's current "oh you're a New Zealand user... i'll stick a sorted.org.nz banner in there for you" approach.
I imagine it will take and index of your sent items and put some relevant content related advertising in rotation too... Particularly because if you were the one that sent the fact that you had a flu... you're really the one that was the target audience.
It really isnt that much to ask. I hope the above gives some understanding so you dont do the whole "fuck that they're looking into my life" thing without understanding what is actually going on.