I am no expert with flash or html5, but I tried to do video streaming with html5, trying to get the little project in a few hours, and could not figure out how to do it. Then, I ran into all the problems with choosing the video format, h.264, Ogg Theora, and there is another one. So, although I am for HTML5 because it is an open standard, I see flash as great technology for the next 5 years, and Adobe has being open-platform even supporting Linux.
Tegra is really exciting, it should give Intel a run for its money as it tries to enter the mobile market. And Intel should be worried. If the same story repeats-- x86 used to be the personal computer chip, and expensive SPARC chips where for mainframes and super computers, and now x86 dominates the PC and server market-- we may be buying ARM-based computers in the future with accelerated Tegra chips. After all, it is better to have 100's of cores with a small instruction set like ARM, than to have 12 or 24 cores with the kitchen sink.