Filesystem recommendations


I have a question on filesystems. Back in the day, I started using reiser3.
It was faster than ext3, and it could be extended without umounting the
filesystem (which has since been fixed in ext3), plus, unlike any filesystem
I have encountered, it could be reduced in size.

Well, now reiser3 is very long in the tooth, reiser4 will probably never go
anywhere, so I'm wondering what filesystems are recommended. Last I heard,
ext4 is stablizing, but it had problems with filesystem corruption, though
that was mid-fall last year, IIRC.

So now, I would like to slowly start replacing my reiser3 partitions
with...something else. There are two options, the old standards, e.g.
ext3/4, xfs, etc, and then there are a slew of new filesystems, such as
nilfs2, btrfs and exofs.

I'm talking about a range of machines, from workstations to servers to NFS
and storage servers with multi-terabyte disks, and a backup server with
several hundred gigs of backups.

Does anyone have suggestions and practical experience with the pros and cons
of the various filesystems?