If you are still running Windows 7 RC (I'm sure a lot of people are because it was pretty darned stable), the time to move on is fast approaching.
From 15th February, warning messages will start, saying that from 1st March Windows 7 RC will shutdown every 2 hours. You really want to be off the RC by then because you will lose any unsaved work.
If you continue to use the RC through the bi-hourly shutdowns, on 1st June 2010 the RC will cease to meet "genuine" Windows criteria and will not be able to download anything that checks whether the copy of Windows is genuine. You'll also lose your wallpaper, but by that point that's the least of your worries! ;-)
I've still got one machine running the RC - that will change this weekend!