Sorry if I came across as negative. The "stuck with" was a reference to ZFS's status as a pre-1.0 PPA, not a reference to Linux filesystems as a whole.
On the other hand, the only in-kernel Linux filesystem that can match ZFS's feature set (for example, resizing a RAID array while the filesystem is online) seems to be btrfs, which probably won't be marked stable for at least another year or two. The latest developments to XFS and ext4, though interesting, aren't particularly relevant if you're looking to build a server like what the article describes.
I'll just note that it is the implementation of ZFS that is pre-1.0, not the filesystem itself. The ZFS filesystem itself has been production-ready for several years now. That said, I might use the current Linux implementation for my non-critical data, but for anything important I'd stick to Solaris/OpenIndiana. There's also a decent implementation on FreeBSD, but I'm not a fan of that OS.
On the other hand, the only in-kernel Linux filesystem that can match ZFS's feature set (for example, resizing a RAID array while the filesystem is online) seems to be btrfs, which probably won't be marked stable for at least another year or two. The latest developments to XFS and ext4, though interesting, aren't particularly relevant if you're looking to build a server like what the article describes.
Still, thanks for the many interesting links!