> Lastly, what's the difference between mameworld.info forums and the mamedev.org
> forums? Do devs appear in both forums?
The mameworld.info forums are completely unofficial and are largely a free-for-all where common sense reigns (don't be a racist/whatever douche) but you can swear and such. They've been around far longer than MAME's current presence on mamedev.org, so it has far more active users, though a lot of us are oldbie retro gaming fans. It's frequented by a number of MAME devs out of habit as there was nowhere else to go when the original forums on mame.net closed down.
The mamedev.org forums are the only truly official forums. However, I have to admit that I don't visit them with anywhere near the regularity that I visit MAMEworld, and I'm a dev. I'm pretty sure that's the case for a number of other devs. But I'm trying to get better at that.