I haven't had any frustration with Vista's memory management... RAM seems to be available whenever I need it, so I'm free to get peeved with other aspects of the OS. The new TCP/IP stack rocks, per-application audio volume memory rocks, backwards-compatibility with existing software has been okay, the HDD backup feature rocks, and the OS seems rock solid. But there are a few things that ticked me off a bit:
Folder Views: Whose computer is this, anyway? I'm a CD Freak; I don't need a Burn icon hogging space that could be used to display folder contents. You need a book to finally get the folder views for the various templates to display the way you want them to... and to make them stay that way.
Activation: I bumped my FSB a few mhz... what do you mean I have to activate again?
Activation: I have two drive drawers and a bunch of removable HDDs... what do you mean I have to activate again?
Activation: I switched one of my SATA controllers to AHCI mode... what do you mean I have to activate again? Hey, what do you mean I have to TELEPHONE someone to get my machine activated again? Whose computer is this, anyway?!
Anyway, no memory management issues for me. Anger management is another story.