I didn't see any recent test for 2013, but it's been analyzed quite a bit, and the 2 links below expand a bit on what I mentioned.

The conclusion on the first one below is that it won't index content loaded dynamically from a javascript file on another server/domain.

http://www.seomoz.org/ugc/can-google-really-access-content-in-javascript-really

Here's the link that talks about extra programming necessary to make AJAX content crawlable and indexable.

http://support.google.com/webmasters/bin/answer.py?hl=en&answer=174992