Discussion of folk buying copies of Windows 7 cheap lead me to wondering just how long Windows XP has left. It turns out that Windows XP Professional (what I have)
has until August 2014 befored 'Extended Support' (read mostly just security bugfixes) ends.
So, not looking likely that I'll ever install Vista, Windows 7, or possibly whatever comes after it. Well, unless there's some pressing reason like an awesome-looking game that needs DirectX10, or another reason that boils down to "XP won't support the hardware (well enough)".
For the record I clung onto my Windows 98 install until it looked like M$ were finally going to kill Extended Support for it (although they ended up giving it another 6 months or so not long after I bought my Windows XP Pro copy). That was some time around the end of 2004 I think, although it's hard to tell as it seems I didn't post about it here at the time.