Is there any very rough estimate of how long it would take to recrawl our site, since we just changed around our entire URL structure. We are 301 Redirecting all the old urls to their new homes.

I would think this happens almost instantly.

It's been over a week, and most of the URLs in the SERPS are still the old ones. We are also seeing some duplicates (such as where the old URL and new URL both appear in the SERPS for the same query), which is super odd since we're 301 redirecting.

You can be sure the search engine has spidered the site entirely. It will take time for it to sort the old from the new, maybe a week, maybe two.

I just noticed the logical naming changes that you made, good move! This will surely help your site out.

Thanks!

I think that crawled soon.