Ubuntu 8.04
So I'm taking a second crack at putting to use all of my storage, after my first failure months ago. Now I'm in Ubuntu 8.04 dd'ing my boot partition onto one of the new drives, and enjoying the Ubuntu LiveCD in the process.
I have to say I'm pretty impressed with Ubuntu 8.04. I've been kinda disappointed in GNOME recent years: it seems to have stagnated and lost a lot of the momentum it had in the early GNOME 2.0 days. For example, the biggest change in the latest version is that the underlying virtual filesystem abstraction was swapped out for a new, different virtual filesystem abstraction - a change that shouldn't have any user-visible effects and even nerds like me have a hard time getting excited about.
But it's actually really cool, in that it solves one of the annoying previous issues of GNOME: that if you navigate to somewhere on the network (CIFS or SFTP), you couldn't expect the files to open in non-GNOME applications, because the files only existed in gnome-vfs, not as actual files that Linux knew about. With the new system, each "virtual" filesystem is represented in a FUSE filesystem already present in ~/.gvfs. I'm using the SMB/CIFS implementation and it seems a lot better than the crappy FUSE implementations I've used before; in fact I think it's the most reliable and user-friendly CIFS implementation I've seen on Linux yet.
If I can get the Linux Aventail VPN client working to RDP into my Windows work computer, I might consider switching back to Ubuntu on a somewhat more permanent basis - especially if I can't get this RAID nonsense working in Windows.