Tara Hunt wrote a very interesting article titled R.I.P. Browsers
I think this point of view is going a bit too far. It is true that surfing on a new generation website gives the impression to have “an OS on an OS”. Take Yahoo! Mail for example, many people are amazed to see its resemblance with Outlook Express. Then why can’t the application just open up without a browser?
There are many examples in which web content is displayed on your PC without the need of a web browser. In this sense, widgets can basically show you anything as long as the content provider offers a feed to subscribe.