Theory: Google is pretty good at figuring things out.

Reality: Google's algorithms, that go through hundreds of changes, tweaks and modifications every year are a soupy mess and their ability to "figure things out" was proven so flawed last year that along with Microsoft and Yahoo, they came up with Schema.org just to address PART of that reality.

Recommendation: Never do anything that could possibly confuse Google if you don't absolutely have to.

Wordtracker for keyword volume and Overture PPC for keyword value were my two go-to resources.  And WebTrends for the painful process of attempting to figure out what was happening on-site.

Personally, I wouldn't try to figure out the impact by looking at crawl stats.  I'd be more focused on end results.  Have we had an increase in organic traffic, or conversions from Google shopping since we opened it up, or has either of these gone down?

That's what matters, and is the only real indicator as to whether it was a wise move or not.

Drew,

Thanks for emphasizing the resource allocation consideration. I mentioned it only in a minor way, yet it really is a critical consideration.