TheJoe: They do. XP is supported until 2014 and only becomes officially obsolete in 2020.
Fenixp: Really? I thought they have dropped support altogether, but they DID stop selling it, right? Right?
Not all at once.
Windows XP SP3 is the only service pack level that has any support. If you don't have SP3, trying to get updates will get you a message telling you to install SP3.
"Mainstream" support for any level of XP ended in 2009. New features, non-security bug fixes, warranty support, and the like ceased then.
"Retail" sales of XP SP3 ended in 2010, and "OEM" sales ended in 2011. But nobody was selling it anymore anyway.
"Extended" support, which amounts to security updates and knowledge base access only unless you're a paying customer, will end April 8, 2014.
http://windows.microsoft.com/en-us/windows/products/lifecycle