Well, I don't think that's too much of a surprise. I think FF13 is going to be kept fairly secretive (other than videos) until it gets closer to release. To add to that, with the announcement of an Xbox 360 version, the (unannounced) release date is probably going slip back further.
It would be pretty cool though to see some live gameplay. Maybe we'll get lucky and SE will release a playable demo before the actual launch, similar to what they did with FF12.