The current date format used on posts is not clear at a glance. It can be difficult to determine if a post happened last month or last year. For example, the two posts below:
Looking carefully, you can see that the first is from April 2014 and the second is from April 14. However, at a quick glance, this distinction is unclear. I believe that it would improve the UX if the year format were expanded to show the full year, instead of using the apostrophe format.