N455UA, which I'm on this morning, has the new seats. My added observation is that the seatback pocket is too small to fit anything larger than an iPad mini or Kindle.
If they made the seat bottoms longer (out toward your knees) and made the armrests a little bit larger it would be a huge improvement. The underseat storage is a bit smaller as well. I didn't notice this on my first flight because I only had a rollaboard.