If you need or want to run Windows (or other operating systems) on your Intel-powered Mac, the leading products in the segment are Parallels Desktop for Mac and VMware Fusion (plus, there's also Sun Microsystems' VirtualBox).
VMware has added a ton of features to Fusion 2.0, many of them aimed at easing OS X-Windows integration. As before, you can drag and drop files and folders between Windows and OS X. But now you can also copy and paste formatted text (not just plain text) from one OS to the other.
You can also create mirrored folders: You can set up your Windows virtual machine (VM) so that its Desktop, Documents, Users, and Pictures folders are actually pointers to those same folders in OS X. When you save a document in Word for Windows to the Documents folder, for example, it'll be saved to your user's Documents folder in OS X, not to your Windows virtual machine's Documents folder. This feature is off by default.
Version 2.0 also lets you enable application sharing, which will make programs in your Windows' virtual machines visible to OS X, and vice versa. (For this feature to work, the folders in which the documents reside must be shared with the VM.) You can share Internet applications in a similar manner.
Fusion 2.0 shone in my tests with both Linux and Windows XP Pro, and Vista. The speed of typical office applications (Microsoft Office 2003 in XP Pro, OpenOffice.org in Linux) was fine, even with image-laden documents and large spreadsheets. Programs loaded quickly, and I was able to run multiple programs at once in both virtual machines without any noticeable slowdowns.
Overall CPU usage has decreased to the point at which you can leave Fusion running in the background, even with an open (idling) virtual machine. On my Mac Pro, a Windows XP Pro virtual machine sitting open in the background typically used between 3 and 8 percent of my CPU; in the prior version of Fusion, that would have typically been 10 to 20 percent.
If your interests lie beyond Windows, Fusion offers new easy install options for Ubuntu, Red Hat Enterprise Linux, and Mandriva Linux variants. Fusion has also upped the list of supported operating systems; you can now install over 90 different OSs, including OS X 10.5 Server.
The new Virtual Machine Library window makes it easy to see exactly what's going on with each of your installed virtual machines. Not only do you see the status of the virtual machine, but the images are updated every ten seconds.
Snapshots make it simple to roll back the state of a virtual machine. Fusion also includes AutoProtect, which lets you set up automatic snapshot creation every 30 minutes, every 60 minutes, or once per day. You can also specify how many snapshots you'd like to keep; Fusion then uses these settings to keep a mix of hourly, daily, and weekly snapshots.
VMware Fusion 2 brings a host of new features to the table, improves performance across the board while reducing CPU usage, supports more guest operating systems (including OS X Server), and does it all for the same price as the original (and if you've already purchased Fusion, it's free). From handling the Microsoft Office suites to playing many older and current Windows games to making it painless to experiment with other operating systems, VMware Fusion 2 is more than capable of handling nearly any task you may think to throw at it.