I'll agree with JohnDoe;  I have Win7 on thirteen machines, and have more Win7 licenses hoarded on the shelf.  I'd predict Win7 will be the inheritor of WinXP's popularity and loyalty, unless Win9 turns out to be a hit.  Win7 has been stable and I've had no problems with programs not running on it.

     @Wolf359:  I think that both Windows OS updates and an antivirus/firewall program are needed;  each is necessary, but not sufficient by itself.  An antivirus app can block most attacks on the OS,  but it can't repair damage once it has been done to the OS, nor does an antivirus program modify the OS to eliminate an OS vulnerability once that vulnerability becomes known.

     Windows updates frequently modified OS components in order to defeat known methods of attack, and also provided a means of repairing damage which a worm may have done before a defense had been devised against it.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

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