Perhaps in response to the approaching release of Fusion, Parallels has kicked their marketing for Parallels desktop into high gear with a new series of ads -
http://parallelsvirtualization.blogspot.com/2007/07/coexist-with-parallels.html
Parallels was first to market by a considerable margin, and thus is already better known than Fusion. A lot of people might not even be aware of Fusion, and think Parallels is the only virtualization software available.
At this point, VMware needs more marketing to build some mindshare in the Mac community.
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