Another reason I'd be interested in something like this: it really, really means people have to commit.
I can't tell you how many events I've created or participated in evens in which the group's Facebook page suddenly has a lot of cancellations and excuses the morning of an outing, often resulting in a cancellation of the event. It sucks.
In one frustrating instance, I put together a group outing for SMORR in Missouri. Being that SMORR is a drive from the Chicagoland area, I created a date months in advance. I was happy to see a lot of people were interested and wanted to go. A lot of RSVPs were "yes". I ended up burning three days of vacation time at work to go.
You can imagine how pissed I was when participants began dropping like flies. By the night before, everyone cancelled. It was extremely disappointing and put a huge dent in my interest of organizing future events.
Even if I don't go — though who knows what two years holds — I hope you get a turnout for this event. It looks awesome.