These Parallels Desktop 7 enhancements are welcome, but I'm not sure they're worth the cost of a $50 upgrade ($80 for the full version) to most users -- especially just nine months after Desktop 6 was released. What might entice you to upgrade to Version 7 is Parallels Desktop's new ability to create Mac OS X Lion VMs, with which you can run virtual Mac instances on your Mac, such as for beta testing or configuration testing.
Previous editions of Parallels let you set up Mac OS X Server VMs, but not VMs of the desktop OS. Apple removed its restriction against desktop OS VMs in Lion (you're permitted to run two Lion VMs on your Mac), and Parallels quickly enabled that capability in Desktop 7. (Note: You still can't create VMs of previous Mac OS X desktop versions, as Apple hasn't changed the licensing terms for Snow Leopard or earlier versions to allow it.)
Virtualizing Mac OS X Lion Unfortunately, Parallels Desktop 7 gives you only one easy way to install Mac OS X Lion on a VM, but it's painful: You download the 4GB installer file from the Mac App Store, which means waiting for one or more hours.
The way Parallels handles Mac OS X installation via the Mac App Store means you can create only clean installs of Lion; there's no simple way to transfer an existing Lion environment to the VM as there is for Windows VMs.
If you're a savvy Mac user, you can get past these issues. For example, you can use the Windows DVD install option to select a Mac OS X installation image from your startup disk or from a USB-connected storage device. But you can't use the Install Mac OS X Lion file that you downloaded from the Mac App Store. Instead, you have to open that application package (Control-click or right-click the Install Mac OS X Lion.app file and choose Show Package Contents), then search for and copy out the InstallESD.dmg file containing the disk image. The installer file is deleted by default once you install Mac OS X Lion, but there are ways to prevent that, as well as to access the hidden copy on your Mac. Apple also has a tool that lets you create your own installer image on a disk or thumb drive. Wherever the installer resides, the trick is you have to install its internal .dmg file, not the .app package file containing it.