Here's my latest for Smashing Mag. It's a pretty compelling argument, and it's something I believe will dominate the "what's going on in web" landscape pretty soon.
It's about how motion is an awesome usability tool. It's about how creating motion in the first place is important, and making that motion look and feel realistic is an equally important step two.
Here's the best way I could sum it all up. These two gifs were replaced by video in the article, but I think they have a lot more impact side by side, on loop. One is how apps open currently, and one is how'd they open with no transition.