What is this "crappy" memory management of OS X that you speak of? When it comes to memory management, OS X is definitely among the best from my 14 years of experience with modern operating systems. For what it's worth, I regularly run two VMs in VirtualBox totalling just over 2gb of guest RAM allowance, on a 4gb machine running 10.6.8, and I don't suffer problems with this. Users of 10.7 claim that it's a wee bit hungrier than 10.6, though I still can't recall the last time I saw anything else than "Swap used: 0 byte" in the Activity Monitor.
I can't seem to find the blog post about the memory architecture in Mac OS X, but it was rather recent, under 8 months ago some guy blogged about the crappy memory management that was used in OS X and why he ended up switching platforms.
I have yet to try 10.7 stuck on 10.6 until the boss allows us to upgrade. This will probably be my next big upgrade before anything else.
