Because the HTML/JS platform is only getting nicer. Almost everyone is already dumping fat clients for web clients, even in the enterprise, and it started way b

Because the HTML/JS platform is only getting nicer. Almost everyone is already dumping fat clients for web clients, even in the enterprise, and it started way before AJAX was even heard of. The advantages of a fat-client client/server app are low latency of the UI, maybe development speed given the right toolset, plus definitely flexibility of the UI for graphics and complicated interactions. Disadvantages though are difficulty of deployment, client platform restrictions, distributing updates/patches. Whereas the traditional web thin client is easy deployment to your users across different platforms, via your single installation on the server. The disadvantage of traditional web clients is that you're restricted in UI complexity and latency is high. But this hasn't stopped so many enterprise and web apps being written (and rewritten) for the web, just to get deployment/update simplicity in place of a fat client. So if you can build a complex UI fat client with low latency and the deployment ease of a web app, you're having your cake and eating it too. I think it really could be different, this time.