People do far better at a task when they understand why they're doing it. That's the reason I won't vote for forcing people to post to #newtohubski.
I would, however, vote for making primer the next step after finishing registration and including a paragraph or two about what to do next. Hubski isn't exactly common-sense for the tone set by an average Internet discussion. A bit of guidance can go a long way towards inclusion.
Speaking of the primer: mk, the primer text runs out unexpectedly at this line:
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Doesn't seem planned.