I should have mentioned that I do run Windows XP Pro on my mac under VM Fusion. Like Parallels, I can have have both Windows and Mac applications running. However, on my MacBook Pro, I find that having Windows open (running in the background) takes up lots of memory causing applications to slow down at times. Unfortunately, my 14 month-old computer will only hold 4 gig of ram. The new ones will hold 8 gig, which would be more efficient for those of us that need to run two operating systems and some memory-heavy applications simultaneously.
I think you're correct in that SP1 will support the importing of AC 2010. I'm sure there must be others that are working in offices that are dominated by AutoCad and need an efficient way to exchange files between AutoCad and Vectorworks. We all want (and sometimes need) the latest and greatest software, but it can be pretty disappointing when the newest versions don't work as hoped.
Look at Snow Leopard in that it supports VW 12, but not VW 2009 (or so I have read). I've been using 12.5 for some time now, but look forward to upgrading to 2010, which I'm sure is happy under Snow Leopard, right?