If something can be done using CSS3 instead of JS, that’s great. Besides the fact that old browsers don’t like it there are no performance drawbacks.
I’m not sure it’s a recent development. The look-what-I-did-only-in-CSS has been a favorite past-time of Hacker News threads.
CSS Zen Garden goes back to 2003!
I appreciate the cool things that are being done, but the post / article title reminds me of the “X things you won’t believe” on trash news sites like buzzfeed. =/