John,
I'm sorry to have presumed Parallels' inneficiency. From the preliminary benchmarks it looks like Parallels outperforms Rosetta, but not XP running natively. Not sure where you found your 2% number though, the only numbers I could find show a difference of 19% in favour of the native or "Boot Camp" version of XP in the performance of a specific Photoshop filter. Yes I know this is not a reliable benchmark, but it was the only one I could find after a quick web search.
Source: MacWorld's article http://www.macworld.com/2006/04/firstlooks/parallelsfl/index.php
It seems that as long as the hardware in question supports Intel's Virtualization Technology then "near native" performance is claimed by Parallels. The Mac Mini tested in the article above may not have hardware support for Intel's Virtualization Technology (though the MacBook Pro and iMac are claimed to support it). Meaning that the MacBook Pro would be more efficient at virtualizing XP than the Mini tested in the link above. However the term "near native" sounds very subjective to me. My experience using VMware virtual machines at work on my IBM dual core office PC to run Windows on Windows (this is to allow InDesign ME and InDesign CS2 to co-exist on the same machine) has shown adequate but underwhelming performance. So please excuse my suspicion until I actually see virtualized Windows performing "near natively" on a Mac running OSX for myself.
Regards,
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