Although I'm late to the party in reviewing Windows Vista SP1, it's becoming widely available as I write this, so now is as good a time as any for my review. Rather than try to cover every improvement in SP1, I'm going to cover my particular experiences. Read my review.
Jeff Atwood at Coding Horror doesn't like Firefox's middle mouse autoscroll functionality, so the How-To Geek wrote a nice tip on how to turn off this functionality. Jeff mentioned that he likes Linux's ability to paste with the middle mouse button, which you can actually do in Firefox. Here's how you do it:
Type about:config in the Firefox address bar.
In the Filter line, type middle to find the middlemouse.paste entry.
Double-click the middlemouse.paste entry to change it toTrue. No when you use your middle mouse button in Firefox, it will paste the text on your clipboard.
Windows Vista SP1 review 
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