Just spotted this bit of news over at Guru 3D.

Microsoft's use of caching servers at Akamai could pose problems for those who have set their Windows system to auto-update and use a hosts file to block advertising or any other web content. Reader Glen Fergus wrote in that his XP system had not updated itself since August 16. On August 18, Microsoft made changes in its DNS so that requests for its website no longer resolved to machines on Microsoft's own network but were handled by caching servers at Akamai.