ComputerWorld published a brief but interesting comparison between Apple Mac OS most popular virtualization solution, Parallels Desktop, and the upcoming solution from virtualization market leader, VMware codename Fusion, providing following conclusion:

Both Parallels Desktop and VMware Fusion are good products. However, it is clear that Fusion still needs some work in terms of its performance and to fully implement its feature set. It also isn’t quite as stable and reliable as Parallels.

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It is also worth noting that the next release of Parallels is slated to offer at least two of those features -- drag and drop and USB 2.0. It is also slated for several more advances including the ability to use a Boot Camp partition as a Windows boot disk instead of a hard drive image file, greatly enhanced network options and full support for CD/DVD drives (including burn capabilities and access to copy-protected discs). There will also be a new mode called "coherence" that will allow Windows applications to run alongside Mac applications without the need for a separate Windows interface...

As a result, it seems that for the foreseeable future, VMware will remain a generation behind Parallels.

Read the whole comparison at source.

Despite the unfair competition (VMware codename Fusion is still in beta), which has been admitted by reviewer, conclusion is relevant: Fusion has been annouced since August 2006 and still has to reach Release Candidate status. Before such milestone Parallels is expected to release Desktop 2.5 and to already start working on 3.0 beta.