A lot of us have heard about RIA's (Rich Internet Applications). They are the way of the future, though even with broad band speeds I think the responsiveness of RIAs needs to be as snappy as desktop applications for RIAs to really take off. They are getting close.
http://www.windowshop.com/ (Amazon run shopping site that uses Flex I believe).
Another trend is the blending between the desktop and the web. Adobe Air is an example, and now Yahoo has come out with their own plaform.
Grrr...I swore off yahoo 'cause they pissed me off, but I guess I will have to check it out.