My Mrs bought her laptop on 13th June so doesn't qualify.

You will be eligible for the Windows 7 Upgrade Option Program if your new computer was purchased between June 26 2009 and January 31 2010, and has Windows Vista® Home Premium, Business or Ultimate. You can order your Windows 7 Upgrade kit from the manufacturers by following the links below.
Details on the Tesco site
http://direct.tesco.com/p/inc/specials/windows7/