One thing that has been interesting to watch is how the VP9 codec has come along. When I posted the first beta, VP9 was experimental, had hardly any application support, and was incredibly slow to encode. Today you can play VP9 in Firefox, Chrome, VLC, and other standards-compliant software. And VP9 encoding…well, let's just say it's a lot faster than it used to be, thanks to multithreading and countless other optimizations.
Here's a test I ran: encode the same clip in the different codecs using some masochistic bit rate so you can really see the artifacts. In this case it's a 1080p clip encoded at 500 kb/s (0.5 Mb/s). I made an H.264 using Premiere's encoder and VP8 and VP9 clips using the plug-in. Here's a close-up screenshot of the results:
You can see VP9 has the best palm tree detail, for the same file size. VP9 is a next-generation codec, and it's available and supported right now. The big downside: encoding VP9 took three times longer to encode than VP8 and eighteen times longer than H.264. But what's one long encode when it means potentially thousands of people who view the clip get much higher quality?
Don't take my word for it. Try it yourself and post your results in the comments.