"I see it being organised and asking for money to spread the word..."
Well, the communications, legal, and administrative staff of many of the national orgs take home salaries; I don't see why these two, working to launch a new enterprise in the secular movement, shouldn't also keep an eye out for their livelihood. Indeed, we can expect more from people who make this their profession, than we might from part-timers doing it on a volunteer basis.
"... and suddenly I feel like "Word" needs to be capitalized, if you know what I mean."
I don't know, no... what's informing or prompting this wariness? Other than a natural healthy skepticism.
"Is there another one planned so I can see for myself (or is this an every Sunday thing)?"
There is a brunch planned for the 17th, and then there will be some sort of Sunday Assembly Boston PRESENTS the Holiday Revels (titled TBD) in December, with monthly Sunday assemblies to begin in January. The 11/5 event was videotaped -- links will be available via the Facebook page, Twitter, and Meetup page.
"Like I said I like the idea of gathering to meet the like minded."
I'm right there with you. With so many worthwhile but risky endeavors, much depends on subtle points in the execution. For example, we all loathe the idea of dogmatic doctrine; but what about a congregation that built itself upon the dogmatic insistence on one doctrinal point of agreement: that "The content of our ethical and philosophical doctrines are for each of us to author, in view of and response to the available evidence, to the best of our ability, and subject to change as fits new circumstances"? That's sort of like what I've seen going on with Sunday Assembly. Rather than shrink away from the model of a congregational community, they're embracing it, and blocking the incursion of coercive or woo-woo elements by DISPLACING them with perfectly agreeable and content-free tenets. Savvy in its way, I think.
I trust that Josiah (who had a hand in planning the event, and who has himself thought long and often about atheist church-like things) will have more to say, if he has the time?