Number one on the list is the complete lack of a mobile view. I have a Lumia 920, and I can see a total of ONE comment on any given blog post. I can expand the replies for that one comment, but I cannpt see any other comments no matter what I do. Show All Comments is not a button.
Number two, again mobile related. It white-screens while trying to load/link my gmail account. It kind-of, sort-of worked for a second, because when I revisited the page it asked me for my username preferences... but when I went to post, it asked me to log in again.
I haven't played with the desktop for long enought to know what I like or don't like, but on WP8 I can come for the articles, but cant read or participate in comment threads at all.
One strange thing... Unable to get past the Login on IE10. Kinja only works on chrome for me.