html is better for the masses. flash looks wonderful but not everyone has broadband to download the large flash site. go with html if you have a retail website
I like flash for intros, but I hate intros, D'oh!
I like flash for games and video (like youtube). Full Flash websites, I always close the website.
for me it is clearly html, because not every user has a flash pluggin or the rights to install one.
My suggestion is to use HTML or PHP. As you know, the flash websites took more time to load because of the file size.