What if the list tdwg-content received a notification from each TDWG wiki when a page changed? These are fairly unobtrusive and presently infrequent (because most TDWG wiki's are inactive). They summarize the change and give links to the new content. I believe that they are set to notify only once a day. I \think/ this can be accomplished without more than edit privilege on the wikis, and if nobody raises major objection, I'll try to implement it for SDD, MRTG, and AnnotationsIG and we can see if it is a help or an annoyance.
Pros: No need to make announcements or comments in two places. WikiLuddites can still respond in the mailing list. No need to opt-in for Wiki change notices. One click to relevant information.
Cons: Default is to summarize changes, so people who want to respond in the mailing list have to proactively visit the relevant Wiki and perhaps cut/paste into their reply. Spammy feeling if a wiki suddenly become very active. Wiki users who do not subscribe to tdwg-content won't see email discussion of wiki pages.
Another possibility is to do this in some other mailing list, perhaps even one devoted to entirely to the notifications. But to me, an active mailing list seems more productive. After all, wiki content is nothing if not TDWG content....
Bob Morris