Windows 10, I do NOT recommend it… yet.
Many of you are getting an icon or a window on your computer offering to ‘reserve’ your copy of Windows 10. I don’t recommend doing it now. The word is that it will be a free upgrade anyway. Further, chances are good that it Windows 10 will not be stable until it has been released for 18 to 24 months. If you buy Windows 10 before this time, expect to have problems and be their guinea pig.