The mobo does have a 1394 connector, but there's no need at this time to consider an external drive, I'm okay with the standard internal installation.
Just for reference, most PC motherboards these days STILL only come with 1394a connectors(Firewire400). If you were using it for an external HD or RAID I would definitely recommend 1394b(Firewire800)
But like Mark I have seen no problem against eSATA, I just haven't used it myself to comment on it, but technically that SHOULD be better than Firewire for storage I believe. Again though, haven't used it so I cant really comment on it.
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