Flex

I’m seeing more and more websites that are completly Flex based.

Example: https://store1.adobe.com/cfusion/store/swf/store/flex/main.swf

As you can see it has a scroll bar and it feels just like a standard HTML based website. Do you think this is simply trendy or is it a real trend, and if it is something that’s here to stay why isn’t Flex included in the CS3 web bundle.

Is there something I’m missing here?