You know what's nice about the Internet, as an end user?You don't have to install the Web.
You don't have to upgrade a webpage.
You don't have to download a whole website before you can begin perusing it.
Some nice examples of actual applications as content:
These are a little data-viz centric, I realize, but hilights (for me) the difference between the old world of content and the new (hint: Its participatory :P)
**OK, this one's just demo-ware, but it shows that just DHTML fun can be had.
To use it, click a category, then select a demo in the list below that, and then click ON the demo picture itself to activate it.