Basically, to send the response they sent you to everyone else they sent the original email to in August, acknowledging that the replacements aren't going to be sent in October as originally expected and that they are currently awaiting an update from the supplier.
That's all. Then everyone that ordered knows what's happening, rather than reading it on here, or sending separate message to Zavvi themselves (as, er, you did).
As daft as it may sound, even communicating that there is nothing really to communicate at this stage is better than not communicating at all, IMO. At least then everyone knows the position and isn't left wondering. It would also save Zavvi from having to respond separately to individual enquiries from people asking what is happening, given that they last told us we would get replacements in October but that time has now nearly passed.