MSN has been tracking users’ browsing habits for some time now. It didn’t matter whether a user deleted their cookies, the MSN cookies were still remaining on the system. These “supercookies” were capable of re-creating users’ cookies after people deleted the regular cookies – evercookies anyone? Read Julian’s blog post about the evercookie threat and how you can remove these nasty cookies.
Microsoft has now (August 2011) removed the code that was responsible for re-creating the “supercookies”. Microsoft has also confirmed that the data from the old code has not been shared with anyone outside of their organisation.