Well the alpha is mostly for testers anyways so that they can see what works, what doesn't and test new mechanics and features, hell most of people in the alpha don't submit stuff anyways as seen by a poll they took awhile ago, but any bit helps.

A play-through or two and most stop playing and its understandable as there really isn't that much to do, especially once you've beaten Act 1 once.

If they go as they usually do their should be a new update maybe around week or so after PAX.