The non-browser browser

Consider the number of websites that use a shit ton of styles, images, advertising, javashit, whatever. All that is shitty cruft that you don't want to have to wade through to get to the important part: data.

Fortunately, many major Web 3.0 Bullshyte websites have RESTful APIs too (mostly JSON), allowing you to gain access to structured information in a consistent way.

Enter stage left: A scriptable, customisable program that, given an interface description for a particular website or data source, will show you the data you want in the format you want.
A true separation of interface from implementation.

However, there are drawbacks. Each data source will need its own interface design (but enough people who care coupled with a few public databases, that will not be a problem). Websites will lose ad revenue. The WWW as we use it will change.

So, /anus/ - is it worth it? Is there a need for such a program? Are there more, more serious drawbacks I haven't thought of? Am I just overreacting to Youtube's fiftieth redesign in the past three months?

What is there to un-ignore, this idea is unscientific and ultimately destructive. They're all accessible by trackable, revocable and eventually billable API keys only, that's even better than them pushing cookies. Its also only usable with VC funded walled garden money pits that inadvertently enforces a computational divide between two kinds of web requiring two different programs, one of them has infinite amounts of money and the other is a bunch of chans, wordpress splogs, small forums and Mentifex manifestos. Its as if this plan would play directly into their own hands. Ah yes, this browser already exists, its the iPhone App Store.