It’s not about HTML 5 vs Flash. They’re mutually beneficial. The more important question is the freedom of choice on the web...
Look at the iPhone helicopter we just saw — why should I only be able to use an iPhone for that? Why can’t you do that with any phone? If you look at what’s going on now, it’s like railroads in the 1800′s. People were using different gauged rails. Your cars would literally not run on those rails. That’s counter to the web. The ‘rails’ now are companies forcing people to write for a particular OS, which has a high cost to switch.
Translation:
We will lower the cost to switch phones by moving the switching cost out of the hardware and into the tooling. Then we will benefit because you will need to buy our tools to write applications and you won't be able to switch tools.
Adobe will make all the tracks the same gauge, but you won't be able to manufacture a locomotive without their tools.
p.s. I upmodded this post because it's important to hear what they have to say, not because I support what they're saying.