Is recent upsurge in talk about DHTML anything new?

How is this different from Outlook Web Access, Netscape's plug-ins, or Java Web Start? I grok the debate between fat and thin clients, and the question of whether thin is bad because it means the end of windows as we know it or thin is good because it means a subscription revenue model. And postulating how and where the industry will evolve is a worthy exercise. But forgive me for not understanding why Google's and Yahoo's recent efforts along these lines constitute a shift in the technological landscape.

In what direction will information worker application innovate in the future? And will that direction be better served by what Win32 offers or what Google offers? If we are moving towards collaborative spaces that requires software that searches, analyzes, and presents "information universally accessible and useful" [sic], then Google has indeed shifted the landscape on the fat versus thin debate. Their web client for information workers may be better able to address these new types of applications than Win32 currently can.

Google currently offers only a free beta version of their API for personnel use. So they are making no revenue on it. But if their "platform" is where new applications take root, then that is a loss for Win32, no?