I voted for 100; by that time someone has established that they're interested enough in the forum that they'll probably stick around (and be a customer, and the special offer is a good customer incentive). I see the Yard as being an inclusive group, and while its notable to make JYD or even Scrapper, they're in the pack by the time they're a Mutt. I might add another requirement though: that someone has posted within the past few months -- even if they contributed to reaching 300K, the special offer probably won't matter to someone who's moved on to other interests.

I didn't read through others comments before I posted, so the recent activity issue has been brought up. The only reason I'd want the cutoff to be a fairly long period is to ensure deployed active duty folks who may not have access to the site aren't excluded.