I was under the impression, based on the advertising, that the 14th would be more like the 13th with errata incorporated. There's the 360-10 spec of course, but other than that the updates sounded to me like bug fixes more than new info. I may get it soon, but then I also teach a class in steel, and we tend to use whatever is newest at the university, not to mention AISC isn't shipping the 13th anymore.