Help! Dynamo newbie here!

I know my mechanical stuff, and I know my battery-powered lights, but when it comes to stuff that connects to dyna-hubs and external chargers, I'm at a bit of a loss.

I've been charged with writing up a short Q&A session for some dynohub accessories...except that I don't know much about dynohubs. (I'm very knowledgeable about everything else they wanted me to write about, though.) All I know are the two biggest brands are SON and the Shimano Nexus series. I'm still doing research to see if lights and battery chargers are interchangeable between the two brands, except that aside from reading their corporate websites and product pages, I'm not sure where to start for things I really want to know, like "are there compatibility issues, and what makes one brand incompatible with the other?"

I can probably play it safe sticking to just these two companies, as the company I'm writing for only has hub kits for Shimano and SON. However, it got me to wondering what other dynamo hub brands are out there - like SRAM, Suntour, and maybe Sturmey-Archer - and if I can actually say that those brands might be compatible with either Shimno and SON. Or are Shimano and SON dominating the dyna-hub market to the point that considering other brands isn't even a concern?

Any help would be appreciated.