If Parallels doesn't add snapshots (almost immediately), it will have a hard time in the market...and will probably go away...
I don't understand why this is such a big deal. Just plug in an external disk, and copy your VM using the Finder. Presto, snapshot. To restore, copy it back. If you have room on the internal disk, copy it there for backup and no external is needed. I just use the Finder's duplicate function on the .hdd file, and restore is just a delete and rename (and another backup duplicate command of course). There's a rumor that snapshots are patented, but that makes little sense since the concept of a shadow file to simulate read/write on read only media has been around for decades -- long enough for a patent to expire, and just deleting the shadow file provides snapshot functionality. Tempest in a teapot this.
For Mac OS X Parallels Users... Think about the comment I made regarding ZFS on the following thread comment: http://forum.parallels.com/thread11069.html
I've created a program that makes it possible for snapshots of VMs to be created, see this thread. I haven't gotten any feedback yet though, so if you try it please reply with any suggestions or problems that you have.
