With build 523.7 (3.0.4) of Safari for Windows (available on Apple Developer Connection (ADC) even with a free account), and using Parallels Desktop for Mac in Coherence display mode, the Safari window lose the focus each time it loads a new URL. It only happens in coherence mode, in window or fullscreen mode it's ok. I also reported that to Apple just in case it's a Safari bad behavior, but as it could also be a Parallels coherence bug, I report it to you too. Note that it doesn't happen with the 3.0.3 public beta version.