Okay - I have had a couple weeks now to play around with the new Flex builder 2.0 beta. One word - amazing! I rarely get excited about technology these days given most "new" things are simply a minor gain on something already done, but quote me on this - Flex is going to be huge. It's not that Flex is obscure now, it is just that once developers and other tech-heads use it, they will probably largely abandon what they are using now for front ends.
During Adobe's technology Summit, I had the opportunity to watch some of my colleagues build a Flickr Photo browser from scratch, using the web API, in about 10 minutes. While I was watching this, my colleague Matt Mackenzie was sitting beside me and not only duplicated it, but was busy making mods. This is stuff that used to take days/weeks using JSP's! The processing model is also perfect given it removes variances for different platforms. No longer will this be an issue as long as the user is using the reference implementation of Flash Player.
Developers - if you haven't used it yet, download it now from here:
Analysts, Press, Media types - this is going to be big. Learn about it now from the same URL.