Our original plan was print 100 copies, sell some at GenCon, some at PAX, and the rest online. Then GenCon happened and we sold all 100 there, so it was time for a second printing. We did 100 more, sold some at PAX, and put the rest online, where they sold out in about 24 hours (with a flakey web site).
We're not planning on printing any more of the basic game, we want to focus on the finished product. The PDF will be on sale again and we'll keep that going until the full version is out.
Basically the Basic Game was an experiment and an outreach and it's worked wonderfully. We've learned a lot about how to do this, which is good since I think the launch of the full book will be even bigger.