No way. We won't see updates at a MacWorld. That would be ridiculously boring. That's something that Apple does on a Tuesday. They do it all the time, so it won't happen in Paris. Heck, I doubt Apple would even mention an update if the MBPs and MBs were updated to Meroms. I don't think that'd be worthy of a keynote or even a mention.
They also won't bother showing Leopard again. Why bother? It's being leaked and screenshots are all over the net.
They might come out with that iPhone or the "real" iPod Video media player. That's always a possibility, I guess. I'm not excited about MW Paris at all. However, I'm expecting a lot for MWSF 07 in January.