Eric,
I was running Revit in Parallels on an early 2008 MacBook Pro and it worked fine. I upgraded to 4 GB of RAM, so I could give 2 GB to the Virtual Machine and 2 to the Mac. This worked fine for beta testing and such, and probably could have scaled up to a simple single family house project without too much trouble. For anything larger than that, I would want a new MBP with a full 8 GB of RAM and Windows 7 x64 as the guest OS. Likely I would run a 4/4 GB split most of the time, and if I needed to open a really big model I give the VM 6 GB. One nice thing with Parallels is the full screen dual screen capabilities. If you are plugged into a dedicated monitor, you can run Windows/Revit full screen on it, and pull Properties and Project Browser off to the second (laptop) monitor. And Spaces works great in this config. A simple keyboard macro switches you to a different "Space" with, say, Mail on the laptop screen and Photoshop on the main screen or something. Really slick, and much better dual screen function than you will get in Bootcamp.
One last thing to mention is that, assuming you go with Parallels, you can put the VM file on your laptop drive, or an external drive. I found a 7200 RPM FireWire 800 drive works really well. Actually faster than having the VM on the internal lower RPM but SATA drive. And lastly, you may want to configure the VM to not backup using TimeMachine. Time machine backs up the entire file every time, and the VM is going to be a BIG file.

Note, if you do go the Parallels route, see my other post as there is currently a bug that breaks the Revit Recently Used Files window. The fix is annoying, but not a major problem.

Best of luck, and welcome to the bright side. Be prepared to be annoyed by Windows foibles in the not too distant future.

Gordon

windows rules!!! death to MAC!!! /flee

Like a Pinto at a stop light, revving it's engine. Next to a Porsche.

Unless we are talking about Windows Vista, which was definitely more like an AMC Gremlin. Or a Pontiac Aztek.

Gordon

I'm on this. I'll should have something up within the next few days that everyone can contribute to.

I run parallels and fusion. One of the posts I wrote up that I want back from the old AUGI is a setting by setting account of both of those. Unfortunately I didn't keep a copy (or at least I haven't been able to find it).