I refuse to use Flash sites for commerce or information gathering. In that context, it makes things annoyingly hard to use, without adding much value.

Flash is great for cutting-edge interactive experiences, but do you really need all of that to look at a bike saddle?

I'm (among other things) a web developer, and I work with AJAX, Flex, Flash, Silverlight, etc. - all the cutting-edge tech. I've made many clients remove unnecessary all-Flash sites. Their traffic goes up, their users are happier, and they get a far better ROI.