>Besides losing the ability for snapshots and suspend, do you see any other significant disadvantage to using the VM off bootcamp?
You mentioned VLK, so for most people the initial Windows Activation hassle leaves a bad taste, i.e. doing it in the right order, adding the Tools and re-activating. Other upgrades/changes sometimes triggers re-activation needing to repeat. This this doesn't apply to just Windows, Adobe products have the same (re-)activation issue. I think Office activation is managed by VMware now (not sure), all my software is Enterprise, VLK or MSDN-licensed.
You might want to benchmark disk I/O, the earlier Boot Camp process for handling IO off the local partition did not perform as well as File IO in OS X which always surprises me. I mean the impact was like 10-15%, which is noticeable. Since I long since dumped Boot Camp, this may be out of date and I will edit this out if it's no longer the case.
Edit: I did remember that OS reinstalls or upgrades in BC can be an issue for Fusion, e.g. XP > Vista or Vista > Win7 in that the upgraded guest looks 'different' to Fusion on the next boot. Seems like it would be easy enough to change the guest OS setting for the Boot Camp paritition to whatever you changed your guest to but remember Fusion makes some changes to the Boot Camp OS on initial discovery. The remedy isn't too bad, it's just deleting the placeholder Boot Camp VM definition so Fusion can change whatever settings it needs to on the re-installed/upgraded guest. This is obviously a corner-case scenario but worth calling out now that Win7 is out and upgrade is a path some users choose.
Edit 2: More possible disadvantages are backups. Fusion-created VMs are files that can be backed up like any other files. Whereas backing up Boot Camp requires something like WinClone or an in-guest backup solution. And although infrequent, migrating to newer Macs requires moving your Boot Camp partition separately, again probably with WinClone.
Outside of these factors and reserving space for Boot Camp and then having other VMs, there's nothing bad with having a BC partition around. :smileyhappy: