Well that's silly. Observers should be trivial, and since the game's already multiplayer, replays should be too. The information communicated between clients is the same information required by replays.
Well, technically they have an observer mode which they showed off during one of their tourneys. Unfortunatly it crashed during the finals and as far as I know they haven't been able to fix that bug. As for the replays I think the issue is that they want to make them cross-patch compatible.