I prefer Ann Arbor Area Marine Aquarists- (A2AMA, AAAMA, A3MA.) Here are my thoughts,
I've never cared for being referred to as a "reefer", or our work product simply being referred to as an aquarium or "fish tank". Certainly no slight is intended toward freshwater or FOWLR
folks, as the vast majority of us started there, eventually ending up with full-blown reefs.
In my mind, there is much more to planning/building and maintaining a successful reef tank than is typically inferred by the term reefer or fish tank. We combine multiple disciplines of engineering including electrical, mechanical, chemical, computer and networking - in addition to physics, fluid dynamics, biology...the list goes on.
Many of us spend considerable amounts of time, energy (and money) learning all that we can, often playing a roll in developing new procedures, products and best practices (i.e. look at the advancements made in the field of LED lighting - the vast majority of which were accomplished by hobbyists - not commercial providers.) We then take what we have learned and mentor those new to the hobby (obsession) along the way.
Paulo makes a valid point about the term Marine potentially excluding freshwater hobbyists. If that was a concern, you could always drop "Marine" and use Ann Arbor Area Aquarists (AAAA lands you a top spot in a phone book listing - not that I think it matters anymore.) I beleive Marine should be included in the name as it more accurately describes the vast majority of the expected content and interests of the participants.
That said, I consider myself a Marine Aquarist who happens to live in the Ann Arbor Area - hence my vote