I was travelling SYD-HKG this weekend and walked through the J cabin on the A330 (33B). I noticed that the seats had been recovered with a much more pleasing fabric. It was smoother, and not made of that plasticky fake velvet. I'm sure it would mean that your clothes don't get stuck on the fabric as you try to slide around on it, and probably be less hot as well. The old fabric was terrible to look at, feel and made you feel so hot. And it looked old even on new aircraft.

Unfortunately I wasn't sitting in J this time so wasn't able to see if there were any other changes to the seat.