Yes, that is my analysis as well, though more modern popular usage of "cult" has negative connotations that do not apply to Mac users (or do they?:D)
The fact is that Apple centered most of its strategy in creating a cult. They nurture this, they feed it and love it to the bone. If anything they aren't different than many other companies, Microsoft included and Open Source movement included. Only... Apple did it better.
I find Firefox and Opera fanboyism (and fangirlism ;) ) annoying too, but my hypothesis is that Apple/Mac fanboyism is more annoying because the culture (or cult) is more successful. On a personal level, it is also more annoying for me because Apple is in direct competition with one of the subsidiaries of "Singapore, Inc." (Creative's Zen line of products), heheh.
As far as arguing over the fanboyism in the mac world... I find that quite entertaining. It's almost a photocopy of a recent thread here over a certain browser. Apparently, now it suddenly becomes annoying.