Recently a communication was sent to Windows XP customers informing them of the end of sales date and what this meant.

Phil, Alex & I, the UK IT Professional team, got our hands on the letter and spent some time trying to understand what they were saying, as well as trying to get the 5 pages down to a few sentences.

So in essence, this is what the "end of sales" means for XP users:

What does this mean for support?

1) Mainstream support continues until April 2009

2) We will continue to provide extended support i.e. security updates and other critical fixes for Windows XP until April, 2014

For full details go to http://support.microsoft.com/lifecycle/

Will I be able to buy PCs with Windows XP after June 30?

We will stop selling Windows XP as a retail packaged product and licensing it directly through major PC manufacturers. Therefore you will still be able to purchase through partners but only until the stock diminishes. System Builders can actually still purchase XP until January 2009. So in essence the larger partners and smaller guys should run out around the same time period
What if I have Windows Vista but want to exercise downgrade rights?

1. If you are a larger business customer buying Windows Vista Business, Windows Vista Enterprise or Windows Vista Ultimate, you have the right to use Windows XP Professional through a customer benefit known as “downgrade rights.” These downgrade rights are also available to all our business customers that license Windows through volume licensing. However if you choose to downgrade, you will need to have access to a copy of Windows XP media with its product key (does not matter if this has already been installed on any other machine) in order to be able to do this. This is great value because it lets you use Windows XP today if you need it and then make the move to take advantage of the additional capabilities of Windows Vista when you are ready without having to pay for an upgrade.

2. If you are a home or small business customer, you can also purchase Windows Vista Business or Windows Vista Ultimate and then use downgrade rights (as above) until you are ready to upgrade to Windows Vista. When you are ready, you are “future proofed” since you already have a license for Windows Vista.

3. If you are a customer looking to buy a low-end system (often refered to as a “NetBook” or “Ultra-Low Cost PC”) that uses very low-end hardware that won’t run Windows Vista, then we are making Windows XP available for some time on these systems. In addition, we have programs to make Windows XP available in low volumes from local PC manufactures—and of course major OEMs have the option of offering these “low volume” offers as well.

Beyond Windows Vista
There are also some questions about what comes next for Windows. Our plan is to deliver Windows 7 approximately 3 years after the January 2007 general availability launch date of Windows Vista.

Our approach is to build off the same core architecture as Windows Vista, so that the investments that Microsoft, our partners and our customers have made in Windows Vista, will continue to pay off with Windows 7. The result is that the migration process from Windows Vista to Windows 7 should be much more straightforward.

Computer Weekly has done a very accurate write up here: http://www.computerweekly.com/Articles/2008/06/17/231094/windows-xp-availability-to-be-extended-microsoft-says.htm