I haven't used my account for about a year (so it's probably expired), but there was a stink a while back about Microsoft creating a Hotmail update which included a check box giving them permission to "share customer information to third-party partners" [paraphrase]. On top of that, they were nice enough to have the box checked by default. So unless one reviewed the user settings every time an update was run, you were unaware of the fact that your information was heading out the back door to who-knows-where. Users weren't too happy about the situation once word leaked out. They rushed to correct the change, but by that time it was too late, and Hotmail inboxes were filling up with spam. Of course, the Hotmail staff had the answer: upgrade to a premium account, which gives the user access to a larger inbox and greater spam-fighting measures.
Microsoft may have changed their tactics since then, but it was enough to sour me for life.