As far as it being the first time we've had a reference to another village ingame, it might be the first direct referebce.

There is the barrel of babies event, but that one has been present in a couple of VV games and while they have to come from somewhere, there isn't any reference to one of the other villages and plus, there are many signs of previous inhabitants (some of whom are still around).

Edit: Actually, I looked at the guide sections for VV2 and VV3 and there actually is at least one event referring to another village. VV2 has an event where two people basically wandered over to that area. VV3 has one similar to this in which an adept builder or something canoed over from the other shore. The page with the events didn't say much about it. VV4 probably has one as well, but I haven't seen it myself and the thread that talks about events in VV4 doesn't mention it.