How well one can solve a problem really depends how well one can abstract the noise and distill to the core of the issue. While this is true in every aspect of problem solving it is particularly true in Software Development. All the rage about AJAX – it is RPC, it is Web 2.0 and every other term coined to make it sellable.
Basically it is an excellent example of abstraction. It enables the decoupling of UI from programming logic. So now the user who interacts with a web application does not have to depend on what is on the server and what is on the client.
If I may speculate, this abstraction may finally refine the web to its true potential of a socio-technical, distributive-collaborative application platform.