In my trial runs of various filesystems, I decided to convert the data partition of my server/devel pc from ReiserFS to XFS...
Steps are quite short. Since convertfs is highly discouraged, I did it the long way:
Since XFS is a bit sluggish, I followed the forum thread at http://forums.gentoo.org/viewtopic-t-488215.html to speed things up a bit. I used the following for mkfs:
mkfs.xfs -l internal,size=128m -d agcount=2 /dev/sda6
The explanation for all these parameters can be found in the forum thread I mentioned earlier.
This allows for a bit more optimalization, since my data partition contains quite a few big files, but also quite a few small ones.