I'm a hobbyist who likes playing with virtual machines and have a new multi core box with gobs of ram and would like to move to a 64 bit distro - - but which one? Current distro is PCLinuxOS, which only offers 32 bit.

What desktop are you used to? The following comments are relevant if your answer is KDE.

I use 64 bit Mepis 8.0 for my main computer. That has very good 64 bit support and a nice initial layout of KDE3.

I've experimented with Mepis 8.5. In my opinion, KDE4 is not really ready for general use, and Mepis 8.5 is a major step down in quality and user friendliness from earlier Mepis versions.

I've experimented with Kubuntu 10.04. I think that is a particularly lame distribution of KDE4, generally worse than Mepis 8.5 (unless you need something new like the nouveau driver that Ubuntu has and Mepis lacks).

I also use several 64 bit Centos systems. Centos is a great distribution, with great support for 64 bit. But I expect it is not what you want and it would be a much bigger step away from what you're used to (from PCLinuxOS). So I think you're better off sticking with a Debian based desktop distribution rather than a Red Hat based server distribution.

pclinuxos is pretty nifty, but I need more. Centos seems pretty complete but is has never been geared to the desktop. I was thinking maybe Open Solaris or PCBSD, except the BSDs don't appear to me to be as well along as the Linux Kernel and distros. The concern with Open Solaris is how long will it remain available? I don't think the differences between RPM and DEB are all that significant. I would like to be able to have 3 or 4 virtual machines up at the same time, and 32 bit systems don't recognize enough ram to do this. I haven't had the best of luck with PAE kernels under pclinuxos. It tends to corrupt my boot sector, which locks me out of everything, and I don't have that worked out yet. Subjectively, Ubuntu and Mint are just annoying. That leaves Debian(mild pita), Slackware(major pita), or maybe Suse(boring) absent anything better. And I would like something as or more suitable. Maybe Stormos, if it ever gets out of Beta?

IMO Centos is good for the desktop as well. It's like Debian(stable).