But thats what this shift to cloud computing is about. Web applications simply shift all difficult computation to the server and deliver the results straight to

But thats what this shift to cloud computing is about. Web applications simply shift all difficult computation to the server and deliver the results straight to the client. As for client-side JS code, your point about the increased resource usage is correct, but moot for the next 5-10 years IMO. Hardware is going to follow Moore's law for a few years at the least, and as long as that happens, the efficiency simply isn't an important factor for most applications. History has shown that (at least as long as Moore's law holds) the tradeoff between developer time vs. running time is constantly shifted to favor developers.