Pros: Parallels Desktop 4.0 for Mac is a very stable program that enables guest operating systems to run on top of host operating systems. Thus, you can run multiple operating systems at the same time. The result is the best of both worlds: you can run Mac OS X normally, but if you really need to run a Windows application, you can do so within Mac OS X without rebooting.
Cons: Probably not suitable for gaming. Windows Vista or Windows 7 RC1 Aero effects not supported (Updated – May 23, 2009)
There were two, maybe three reasons why I did not make the switch to a Mac sooner.
(1) Expense: At first blush, a Mac appears to be so much more expensive than a Windows PC.
(2) The cult of Mac: Mac owners frequently rave about their machines like they have found religion. Being a naturally skeptical person, I did not want to join the crowd.
(3) The unknown: My job requires that I work with Windows. Would using a Mac cause more heads that was worth? Would switching reduce my productivity?
Regarding (2), there is no doubt that Mac users are a bit rabid about their computers. I remember thinking to myself a long time ago, "Who cares? They are just computers. If you're the type of person who intentally does the opposite of a trend, I can not really help you there. Yes, Macs have a reputation for being trendy. Deal with it.
Now, regarding (1) and (3), the answer to (3) ("Productivity without Windows?") Actually justifies (1) ("Expense"). My job requires that I work in a Windows environment during the work day. Beside Mozilla Firefox, Microsoft Office is the program that I used for the majority of my day. Before I made the switch, I tried using Open Office as a substitute for Microsoft Office. While Open Office (especially the excellent version 3) will work in a pinch, I simply could not submit * .doc (Microsoft Word format) documents that had been edited in Open Office.
The reason? My work requires that I use some pretty complicated Word templates that just did not quite translate.
The perfect solution presented itself: desktop virtualization.
Parallels Desktop 4.0 for Mac allows you to run Windows on a Mac without the need for rebooting. In a nutshell, Mac OS X is your "host operating system." You can install and run instances of "guest operating systems" within your host operating system. Windows is actually running in a window (or full-screen, if you prefer). Thus, you are running a virtual computer within your host computer.
The excellent "coherence mode" allows you to run Windows applications side-by-side with your Mac OS X applications. Imagine having Safari AND Internet Explorer running next to each other in OS X. Yep, it looks weird, initially.
The setup process was reliably painless. Basically, you install Parallels as you would any other software. Then, Parallels guides you through the Windows installation. Then, you can also install your Windows applications, like Microsoft Office. Now you're running a Windows virtual machine on your Mac!
How does this justify the added expense of a Mac? Well, I look at it this way. If I buy a PC, I'm going to be running Windows or Linux. There is no real legit way to run Mac OS X on a PC without violating the End-User Licensing Agreement (EULA). However, if I buy a Mac, I can run Mac OS X AND Windows, so I'm kind of getting two computers for the price of one.
(1) After you have installed your guest operating system (eg, Windows XP, Vista, Ubuntu, etc.), make sure you install "Parallels Tools." You can find guidance from the drop down menus or do a quick search in the online help. Parallels Tools allows better integration between the host and guest operating systems. For example, without Parallels Tools, you are constantly pushing different key combinations to release your mouse cursor from the host operating system so that you can use the mouse with the guest operation system, and vice versa. Parallels Tools makes that transition seamless. Just point where you want to go and the program will release and engage the mouse for you.
(2) Please remember that if you're running Windows on your Mac, you MUST take the same precautions as you would if you were using a PC. This means that you should install antivirus and antispyware programs in your Windows virtual machine.
(3) You can install a wide range of 32 or 64-bit operating systems as guest operating systems, so you are not just limited to Windows. Currently, I have Windows XP, Windows 7 Release Candidate 1, and Ubuntu Linux.
(4) Because you are running a guest operating system in a virtual machine, program performance is not going to be as good as if you were running the programs natively. Parallels is probably not the best option for graphics-intensive gaming.