For example, this glitch has been around for weeks:
http://dirkjan.ochtman.nl/files/newsblur-glitch.png
I'm also not sure it's quite fast enough yet. I've used FeedDemon and Reeder (and NetNewsWire before that) for so long I'm really used to low-latency feed UI. I think web UI can match that, but NewsBlur isn't quite there yet.
I also think the new design, while much better than the old design, is still quite heavy, in the sense that there is a lot to take in, lots of little details. Personally, I really liked the more sparing design in for example Reeder for the Mac. It would be great if there was an option in the NewsBlur UI to point to a stylesheet (or an inline <style> block) that would allow me to play with customization a bit.
Of course, I also haven't found anything better so far, so it looks like NewsBlur will still be my reader of choice for the foreseeable future.