You probably already ask you : "which filesystem can I use on my web servers or database server ?" Usually you will use the well know Ext3-fs but what about the others ?
I will just try to give you some clue about some other common filesystems. The filesystem aspect of your server is really important and your choice will vary with your running application. As exemple, a mail server will have more performances with a Reiserfs filesystem than with Ext3-fs.
You can have a large list of existing filesystems on wikipedia: [http://en.wikipedia.org/wiki/Comparison_of_file_systems]
An interesting banchmark about Reiser4 : [http://www.namesys.com/benchmarks.html]
In the case of a MySQL Server you can try to benchmark your own server with the excellent tool [SysBench] and read this good article on MySQL Website: [http://dev.mysql.com/books/hpmysql-excerpts/ch06.html]
Here is a complete benchmark done with SysBench with a MySQL Server 4.1 on various filesystems where we can see the High Performance of XFS in a MySQL Environment: [http://howto.x-tend.be/MySQL-FileSystems-Benchmark/x45.html]
To conclude about filesystems, there is not a "best filesystem", as any tuning performance aspect on a Linux/Unix box your choice will depend on your workload, your data integrity needing, the requested size, the disk characteristics, journaling needs, etc. Important things is to well understand your server bottleneck (you can use iostat and dd) then you could define your needs and choose your filesystem.
Personnaly, my databases are now running with XFS, my mailservers with ReiserFS and my web servers in Ext3-fs.
NB : Another important point will be to choose the correct schedule, but nowadays the default one is generally the good one (cfq : Completely Fair Queueing. Here is a good (old) post on RedHat web site : [http://www.redhat.com/magazine/008jun05/features/schedulers/]