The underlying problem in my opinion is that changes to WordPress are not very clear. Yes, you can lookup a changelog, but apart from a nice story about some jazz artist and a couple of screenshots of the new media manager, there isn't much to be found about this snazzy new feature (post formats, that is). Also whenever a new feature is added to WP core, the lazy documentation team of WP is ALWAYS late with updating the documentation regarding new functions, etc. They drop an entire new theme every year, but they fail to properly document important changes well in time.

If they would've promoted post formats better, maybe more developers would use it.