Meetup isn't free any longer. The interesting question is how many organizers of meetings will be willing to pay (or at least front, pending contributions from members) $20/month, or even $10/month to keep using the service.
We have here an exciting empirical test of the dollar denominated size of the barriers to group formation so eloquently explored by Mancur Olson in The Logic of Collective Action.
I predict the demise of my local Slashdot meetup — which I've never attended and which from the look of it I'd guess has fewer than six attendees most months.
Changes – Meetup.com: I'm proud to announce that thousands of Meetups are growing and becoming a vital community resource. In fact, the number of Meetups is up 50% this year so far! We couldn't be more excited about the potential for more great Meetups, including yours.
Everyone asks “How does Meetup.com pay its bills?” That question is even more important as we plan new ways for you to grow your group and have better Meetups. To get there together, we are introducing a required small monthly Group Fee to be paid by Organizers.
Do all members pay? No. Organizers pay the Group Fee to Meetup.com and may ask their members to chip in. It's up to the Organizers. The fee is per group, not per person.
How much & when? The regular Group Fee is $19/month, but Organizers of current groups get a special 2005 rate of $9/month if they pay now.
Why a fee? Because we want to be most focused on the people. Nobody else. As Bob Dylan said, you “gotta serve somebody.” Well, if we gotta serve somebody, we prefer it to be you. We're here to help you succeed at growing great Meetups and trust you to understand that 'there's no such thing as a free lunch.' This is all we do, so our success is tied to your success. We intend to earn this fee.
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Any new benefits? Yes. All members of groups get 1-to-1 email! Plus, we'll ship (mail, not email) materials to Organizers, customized for your group, to help you attract more members. Also, groups get new tools to pool their money to make better Meetups.