You'll be able to see how all this works for yourself in a couple weeks (ish). A few short notes...
I'll be writing up a bunch of conventions and best practices for sharing/publishing content. My target was to have this ready by the big December release, but it's going to be delayed until late in the month (see my P.S. below). You WILL want to review this list, and you WILL want to make some tweaks before anything is deemed "done". I'm guessing that there will be a few things that will be more than just tweaks, such as converting everything to the proper game system structure.
The reason for this list will be to ensure that content from different users all integrates smoothly with each other. I don't think there's anything in the list that will be surprising to anyone. The vast majority of stuff is things we've outlined in assorted places in the past. But having stuff work smoothly for users far outstrips having something out quickly in terms of importance - in my opinion, at least.
Game system conversion has been getting lots of testing by us internally. It's going to be in the hands of the Beta team in an interim release we're putting out in the next couple days. If they find anything we've missed, we'll get it fixed. So it's going to be in place for the big December release.
I don't know if what you're trying to do with the Bestiary is an appropriate approach. To be honest, I'm not 100% clear on what you even described - which could simply be due to all the meds I'm taking right now to keep going. Be aware that the level of granularity you can easily control is NOT individual topics, which sounds like what you want, so your ideal scenario may not be feasible. Bring this subject up again after Christmas and we can work through the best way to achieve the end goal you're seeking - or get as close to it as possible.
The export/import mechanism has the concept of versioning built into it. But I'm not sure it's designed the way you specifically want it to work. The design WILL support things like errata from publishers, so it will allow you to achieve the desired end result. You'll need to wait until you can play with it a bit to see how it actually works so you can utilize it appropriately.
There is NO automatic delivery of anything to anyone. That was the original plan, and is still the long-term plan. However, please remember that we decided to go with an alternate approach that is built around the export/import mechanism. As indicated previously, that has some huge benefits and some limitations. The key limitation is that we'll make updated versions of content available when errata is needed, but users will not get it automatically. They'll need to download the new version and update their copy of it within their realms.
Another ramification of the alternate approach - this time a big benefit - is that we don't need to spend many months rolling out everything in multiple phases. We're not going to release everything all at once, but technical complexities with this approach will be greatly reduced. That's always a good thing.
Hope this helps!
P.S. I've been extremely sick for almost three weeks now. I need to stay focused with the severely limited energy I've got so that we get everything out before Christmas. I'll delve further into all this stuff once I'm healthy and the ginormous release is in everyone's hands (i.e. after Christmas). Thanks in advance for everyone's patience.
