For almost a year, we've covered the ongoing rivalry between Parallels Desktop and VMware Fusion, the two leading ways to run Windows on an Intel-based Mac without rebooting. Last week, the competition escalated yet again as both products received major new releases. And, just to keep things interesting, Apple also released another beta of Boot Camp, their official dual-boot solution for running Windows.
VMware Fusion Beta 4 -- VMware has released the fourth  of their Fusion virtualization software. The biggest news in this release is that Fusion has outdone Parallels Desktop's Coherence feature (for now, at least) with a feature called Unity. Both Coherence and Unity free Windows from running in a separate box, putting windows from both Mac OS X and Windows on equal footing - and giving Windows applications their own Dock icons. However, Coherence puts all windows from Windows in the same "layer," which is to say that you can't put a Mac OS X window between two Windows windows; switching any Windows window to the front brings them all to the front - and Exposé groups all Windows windows together. Fusion's Unity has no such limitations; it not only provides full support for Exposé but also adds drop shadows to each window, for a much more Mac-like Windows experience. In addition, Unity replicates most of the contents of the Windows Start menu in your Mac menu bar, unlike Coherence, which displays the whole Windows task bar within Mac OS X. On the other hand, Unity currently works only with Windows XP, whereas Coherence already supports Windows Vista as well.
Beta 4 also gives Fusion the capability of using Boot Camp partitions with Windows Vista installed. (Previously, only Boot Camp partitions running Windows XP were supported.) This support is still considered experimental, however, meaning users must reactivate Windows Vista each time they switch between Boot Camp and Fusion. Fusion's Boot Camp support received several other bug fixes and enhancements in Fusion beta 4 as well, including automatic updating of Fusion's drivers when running Windows from a Boot Camp partition in a virtual machine. Other improvements in beta 4 include improved performance, a customizable tool bar, and support for Apple 30-inch Cinema Displays. Fusion beta 4 is a 167.4 MB download.
Parallels Desktop 3.0 -- Meanwhile, Parallels has kept busy on other fronts, and their newly released  provides a number of major improvements and new features. At the top of the list is the long-awaited support for 3D graphics, which finally enables gamers to consider Parallels as a viable alternative to Boot Camp.
A new Snapshots feature lets users save the state of their Windows virtual machines at any time, so that they can install new software or make other changes and then easily go back to the system's earlier state if crashes or serious problems occur. Another new feature, SmartSelect, provides the capability to associate file types with particular applications in either Windows or Mac OS X - so that, for example, you could double-click a .txt file in Windows and have it open in TextEdit under Mac OS X, or double-click a .doc file in Mac OS X and have it open in the Windows version of Word. And Parallels Explorer provides a way to view and access files stored in your Windows system even if Windows itself isn't running.
Among the many other changes in version 3.0 are improvements to Coherence, Boot Camp support, Shared Folders, and USB support, plus hundreds of bug fixes.
This is the first paid upgrade to Parallels Desktop since its release. The upgrade costs $50; new copies remain priced at $80. Parallels Desktop 3.0 is a 78.3 MB download.
Boot Camp Beta 1.3 -- Lastly, Apple released , a 274 MB download. This latest version supports the newest Macs (including, presumably, the new MacBook Pro models introduced on 05-Jun-07). It also adds support for keyboard backlighting on MacBook Pros, pairing of Apple Remotes (for those who have more than one), and improvements in several areas, such as graphics drivers and international keyboard support. Apple recommends the update for all current Boot Camp users. As in previous versions, updating requires burning a new Mac Windows drivers CD or DVD, restarting under Boot Camp, and installing the updated drivers.