As Microsoft pointed out already, support for Windows XP will stop April 8, 2014. This is less than a year from now and even if so, some of you probably think that this might not be an issue, since the operating system is still going to be useful afterwards. As much as I can agree on the "useful" part, there are things that might pose concerns.
One of them and really the most important one is security. Due to Windows XP reaching it's end-of-life (EOL), security patches will not be made available. Because different versions of Windows share the same architecture and with it the same vulnerabilities, releasing a patch for one system, but not another poses a huge security risk. Patches for newer operating systems could be reverse engineered to find vulnerabilities, which would be used by exploits to attack users with EOL software.
Is this a valid concern? Absolutely. Microsoft is clearly desperate to migrate XP users to newer versions of Windows. Not just for the new revenue, but also because unpatched, millions of PCs can become easy targets to host botnet and other types of malware that can disrupt the modern PC ecosystem. Because attacks drastically evolved in the past few years and have changed in nature (for instance there are less viruses, but more phishing attacks), Windows XP isn't equipped to handle these threats as it's security model is outdated.
So if you still own machines with Windows XP or an older operating system, it's the appropriate time to look around and migrate to something newer.
Thread inspired by this blog post.