Not really a full review, but an initial impression of Safari 3 for Windows.

• It’s FAST. I know Jobs harped on this during the keynote, but it is definitely the snappiest browser that I’ve used on windows. It has none of the UI sluggishness that Firefox has.
• Japanese input doesn’t work. Not in the UI, and not in any of the web pages. I guess it’s still in the works.
• Seems to be somewhat memory intensive. Four tabs brings it to ~190M in my task manager.
• It’s got a super simple bug reporting interface. Open source programs should do this.
• It’s got OS X’s font smoothing on Windows. I detect a little bit of color fringing, but it still looks pretty good.

Overall, I think it’s a strong candidate to replace Firefox for my home usage.
One more annoyance: It appears not to support my thinkpad’s middle button scrolling functionality. I’m not sure if the fault is with Safari or Lenovo. The middle button scroll doesn’t work in a lot of apps..