Clearly there are not enough experienced HTML5 Developers in the market (yet), so we'll need to be creative in our hiring efforts.
So the question is what the profile looks like for that model developer who can learn the necessary skills on-the-job as efficiently as possible.
Here are the options we have considered--really just the two obvious and opposing models.
1. Hire Flash developers
disadvantage: they will have to learn not just a new language but also a new development environment, because of the idiosyncratic nature of Flash Builder every component of an HTML 5 Dev environment is likely to seem new and unfamiliar
advantage: already fluent in client-side development--the tasks remain the same only the language has changed.
2. Hire the most talented developers available
disadvantage: latency--most or all of their time for (8-12?) weeks should be spent in a pure learning mode with no other demands on their time.
The best answer to this Question might offer a third recruiting model, or it might present a more refined analysis of the two presented below. In other words, i did not intend the prior discussion to constrain the responses in any way.