In the RC0 release of Hyper-V, you may recall, you had to use the same QFE to Windows Server 2008 host and guest machines to get the Integration Component versions matching.
In RTM, you simply need to choose the Insert Integration Services Setup Disk option from the Action menu in VMConnect, just like you do for Windows XP, Windows Server 2003, and Windows Vista.
However, after you get the ICs working and you connect up to Windows Update, the Hyper-V QFE for Windows Server 2008 (KB950050) is still listed. That little logical paradox causes you to check which QFEs are actually installed on your system, and you find that KB950050 isn't in that list.
What sort of crazy voodoo magic is this?
Well, according to Occam's Razor, the simplest answer is typically the correct one.
The simplest answer in this case is that Windows isn't lying - KB950050 isn't installed. For RTM (actually, this happened in RC1), we added another QFE to the mix so that the standard way of installing the ICs (the VMGuest.ISO, which is what gets inserted into the VM's DVD-ROM drive when you click Insert Integration Services Setup Disk) worked for Windows Server 2008.
Since the RTM update actually contains an updated VMGuest.ISO file, it would be impossible for us to put the RTM update in the ISO (it's a classic "chicken-and-egg" problem).
So, we added another QFE that just contains the Integration Components and nothing else to make life easier for all of you. You can still apply KB950050 if you want to. In fact, you can just apply KB950050 if that's your thing. Or, if you want to be totally up to date, you can apply both of them.
Ok, now I'm really going to the ship party. Honest.