Another anecdote:  I was talking with a friend today, and he thought that non-Ultimate versions of Vista limited RAM usage.  I realized right away that he thought that because he must have come from a non-Ultimate Vista RTM to Vista Ultimate SP1, and of course SP1 brought the ability of 32-bit Vista to recognize the presence of all of the RAM in the system.  I explained to him how to find the actual amount of RAM available to the system, and gave him some information about total addressable memory and how video RAM came into play...  My point here is that even if the different editions are perfectly innocent they still have a lot of negative effects, even if in this case the real problem was a user with an incomplete understanding.  The victim in the end is Microsoft's image, fair or not.