I've fully made the switch. Instead of traveling with 2 laptops (a Dell Latitude 610 and a PowerBook G4), I've consolidated to a single machine: a 17-inch, fully loaded MacBook Pro. The tipping point for me? The ability to do real .NET development on the Mac.
Of course, I've seen and heard all the stuff about Parallels and how good it is: many orders of magnitude better than Virtual PC, which must create a virtual set of hardware on which Windows can run. Parallels (and the upcoming VMWare for the Mac) take advantage of virtualization hardware on the Intel chip, so you really do get near native speed when running Parallels inside OS X. Notice: not dual booting, but running Windows in a window inside OS X. But, I'm on a .NET project, and "it almost runs good enough to do .NET development" isn't quite enough. Thus, my hesitation up until this point to take the plunge. Well, I'm hear to say: it works as advertised. Building our project in Parallels on the Mac is essentially as fast as building it on the single processor Dell. The build time is within seconds of one another (for an 8 minute build).
But there are always things that you can't read about in reviews that still cause issues. I've been here before, and know that there are lots of little hidden gotchas. When I decided to move everything over, I reserved some time for glitches. And you know what? I got that time back, because I ran into very few minor ones and no major ones.
Here's an example of something you won't read about but is a huge deal if you are planning to use your Mac for .NET development. For a real .NET project, you must have (of course) the Windows XP operating system, a database server (MS SQL Server), and Visual Studio, including all the 3rd party components required by your project. For our application, you also need Office. How big do you make your virtual disk? This was a very important question in the VMWare days. Like "real" hardware, VMWare virtual disks (at least in the last version I used) cannot be re-sized. Once you create the disk, you are stuck with it. When using VMWare, getting that disk size right is critical. Not in Parallels. Parallels includes a utility that allows you to resize the partition. I started with a ridiculously optimistic 8 Gb drive. I quickly ran out of room. So, I used the Parallels utility to make the drive bigger. But here's the part you can't read about anywhere: once you start the virtual Windows back up, it views that new space as "unpartitioned", meaning that you can't use it for anything yet. But, Windows on Parallels is so Windows that you can run Partition Magic on that newly resized virtual disk and make your main disk bigger. I've done it 3 times now (and am now up to a 20Gb partition for our project).
Here's another illustration of the Window-y-ness of Parallels on OS X. I had some problems with the database setup, and Brian (our DBA) was kind enough to take a look for me. He's in London; I'm in Chicago. I started up Windows, gave him the IP address assigned by DHCP in Chicago, and he VPNed into our network and ran my Windows install via Remote Desktop. He never realized (until I told him later) that he was running Windows on top of OS X.
This represents a watershed event. The MacBook Pro + OS X (and it's siblings) are now the only machines that run every modern operating system. For consultants, that's huge. We can now go into any organization, find out what they are running, and fit in exactly. Your servers are running Ubuntu? No problem, I can create a virtualized version here on my machine. Red Hat, Windows Server 2003, Vista...you name it, I can now run it. The Mac has changed from an artistic, boutiquey machine to the ultimate Swiss-army chain saw for consultants. If I were Dell, I'd be worried. OS X and the wonderfully designed hardware make for a significantly better user experience. And now it's the power users machine of choice. Maybe I should buy some Apple stock...