I've tried to stay out of this debate so far but I'd like to add one point: In my experience, the performance of H.264 playback in Adobe Flash on low-end comput

I've tried to stay out of this debate so far but I'd like to add one point: In my experience, the performance of H.264 playback in Adobe Flash on low-end computers is simply unacceptable. Pretty much any other option offers way much better performance: HTML5 H.264 in Chrome, Safari or Silverlight H.264 playback. I don't know whether it's their version of the H.264 codec or something else in their rendering pipeline but it doesn't really matter anyway. We're a business-to-business shop that need to deliver web-based video content to our business clients. What we care about is our clients reliably being able to play back video on any of the thousands of their shitty underpowered old Dells. This is why they pay us so we get to come to work tomorrow. Still, we like to think that we do the right thing if we can so we would love to use standard, open technologies but this whole mess around HTML5 video codecs (and the fact that Flash is just way too slow on our clients' machines) forces us to use Silverlight instead which unfortunately also means that we can't support Linux boxes or any portable devices.