Facebook Places is Facebook's foray into the location arena
Badges and tags from other apps will transfer over to Facebook as well, and you'll eventually be able to add and tag venues using Facebook. No word on whether those venues will transfer to the other apps, but I imagine they eventually will. The read API for Facebook Places has launched as of today, and write and search functions are still in beta.
So, what do we make of all of this? Will Facebook make location into more than a passing trend? Does this make checking in more fun and useful, or does it just add more spam and give Facebook even more of your personal data?