Well "guilds" is a very wide term in the context of MMOs. Different MMOs allow for different accessibility and features when they implement such a general sounding feature as "guild support". In a way Braben has already built a "different" type of MMO because of the 3 seperate modes all able to equally influence the BGS. Whatever he puts in next will by definition be different to other MMO's because of the 3 modes being equal as far as the shared BGS is concerned.The guilds thing, he constantly said he didn't want them and wanted a different kind of MMO; but that was when he was trying to raise money and I have a feeling he said many things to many people which have turned out to be snake-oil.
Plus, all we know so far is that Squadrons, i.e. FD's definition of out of game player groups, will be able to have mobile docking ships for repair/refuel/rearm. Too soon to tell what this actually means for the game in my opinion. I'd need more info from FD before I can decide whether this will be a good, bad or indifferent addition.