Over the past few years, web developers have increasingly focused on the front end, moving more and more critical application logic from the server to the browser. I've been pretty skeptical of this shift, for a variety of reasons. Browsers still vary widely in capability, so you can only really use the lowest common denominator of your target audience. If your target audience is young, wealthy Americans, you can safely assume they have very capable browsers. And that's great for the many startups trying to reach that market.