First, there's no such thing as "digital jitter". There's just jitter. Jitter is variations over time between the resultant signals in a system. And, just as I said, so long as the jitter doesn't result in a zero looking like a one and vice versa or the timing being off by a full period, the receiver will compensate. That's the whole point of using digital systems when transfering and communicating data. Transmitting a piece of data in digital form takes 8x the bandwidth as analog. However, when you only have two states, there's not a lot of possible error.
In order for a digital transmission to result in a missed bit based on jitter, you need half the period of the signal's worth of jitter. If you've got that much error, you have bigger problems than TOSLINK v. Coaxial.
More info on clock management from one of our app notes:
http://www.onsemi.com/pub/Collateral/TND301-D.PDF
Incidentally, no one even thinks about jitter in the design world until they're over 500MHz.
