People like apps because installing and opening an app doesn't make them feel stupid. Remember the ReadWriteWeb Facebook-login debacle? Even the users who didn't make the same mistakes as those folks still feel frustrated with all the steps and layers in between them and what they want. And don't get me started on URLs.
People don't want browsers - they want Facebook. They want YouTube. We don't need better browsers; we need the Cocoa API to be cross-platform (and stop sucking).