> Ah, you mean the flavour of the month?

That's a bit unfair. There are many mature(upwards 5 years of continuous development) UI components for javascript. Charts, Visualization, Data grids, UI Binding and pretty much anything an application would need are taken care of by some high-quality JS libraries.

Sifting through the various libraries to find one that fits the application is vastly preferable to having to write it by yourself.