Great article comparing ReiserFS, JFS and XFS
 

Here is a great article comparing the 3 journaling filesystems currently available for linux.

http://www.osnews.com/story.php?news_id=69

Here are a few links for more info:

ReiserFS from Namesys - http://www.namesys.com
JFS from IBM - http://oss.software.ibm.com/jfs
XFS from SGI - http://oss.sgi.com/projects/xfs/