My nice 22" 1680x1050 monitor that was attached to my Mac mini just died (grmpfh!) and I need a new one. The 1680x1050 resolution seems a bit out of fashon today and more or less only full hd monitors are available (within a certain price range and the prerequisite to be an ips or pva panel). While the 64 MB VRAM of the mini felt comfortable enough for 1680x1050 and 2-3 screens opend (I rarely run out of VRAM) I have my concerns about the higher resolution. Do you guys with a full hd monitor and 64MB VRAM have issues with that? Or are that additional ~18% pixels easy-peasy and no issue?

Well had my 1st Mini on a 24" 1920x1200 monitor (so even more than full-HD) and it was useable even for such a multi-window messy as myself....

I noticed that at least some Mac minis - including mine - are a bit picky about the FullHD 1920x1080 resolution which seems to be related to the integrated DVI transmitter (analog VGA is fine - but you don't really want that even if it is acceptable with a proper cable).
IMHO it shows that this machines were never designed with FullHD in mind which no doubt is a sort of common native monitor resolution nowadays.

My 64M model works fine with FullHD monitors, but my 32M one seems to be picky.

In vmem usage 64M version is good in my use for 1 enhanced screen (Ambient) and two non enhanced screens (OWB and ShowGirls for example), but if I add more screens of have more in enhanced mode then it starts swappng the mem with slowdowns in screen switching. New big windows on Ambient may get some slowdowns occasionally too if you have many windows open, but if you'd use all screens as non enhanced, then there wouldn't be any problems. Still it's quite ok with some enhanced mode screen, even if not perfect...