Actually some of your observations are imprecise, but this is because you
compared wrong things.
Flex is to general name. So, if you are talking about Flex framework - yes,
I would imagine it is slower when rendering simple stuff as compared to
HTML, though it may compete against HTML when it comes to complex layout.
However, if we speak about normal AS3 it will be significantly faster than
Canvas, though, for the very basic tabloid-like pagination it may not be
so... There is a problem if you want to measure SWF size against HTML. In
general, SWF would win, because it is a binary zipped format. However, often
times people tend to overuse this feature, so they put lots of content in.
If you want to see a what I would call a good example of using flash (not
Flex framework) here it is: http://www.pixlr.com/editor/ this site loads at
average 2 times faster than any VBulletin board and about 5 times faster
then Gmail :) and it is sophisticated enough to be compared to the sites
I've mentioned.
Also, regarding your research. Flash isn't about delivering textual content,
and although I think I remember Adobe promised Ctrl+F integration in Flash
Player 10.1, I don't think it is going to change the situation.
So, if text accessibility is a core requirement I would think that you would
be better of with HTML and JavaScript.
