Well, if you're looking to develop for a future AmigaOS or clone, feel free to ask here about any of the solutions, theres a bunch of developers on here. If you want to ask technical questions about a specific system, the developers of OS4 hang out on
Amigaworld.net, and i'm sure there are a bunch of MorphOS developers at
morphzone.org.
As for the factions, its not as bad as you'd think. In real life, we all pretty much get along, but web forums can get heated and seem like a war zone, mostly due to a minority of idiots.
I see you're in the UK. Well, we're organising an OS4 on tour date in a month or so, where you can come along and try it for yourself. That is, if you can get down to the south west...