Which FS for multi-TB RAID6?

[Zoltan Boszormenyi <zboszor freemail hu>]

Hi,

in about 4 month I will build a new machine that will
be used mainly for PostgreSQL development and testing.
The disk subsystem will be a 8-port 3Ware 9650 fully
loaded with 750GB disks in RAID6.

F10 will be already released when it comes to installing
an OS on the new machine so I will use it.

Which FS is suggested for the PostgreSQL partition?
XFS? JFS? Is ext4 stable enough yet?

Best regards,
Zoltán Böszörményi