A good comparison is document.getElementById. How many people actually use this method directly? Most developer have a favourite JavaScript library that they include by default whenever they start writing a web page that uses JavaScript. Even those that don’t use a JavaScript library will probably create a short-cut method to access the DOM in this way. Another good example the the XmlHttpRequest object.

My bet is that exactly the same thing happens with WebSockets. At the moment the support for WebSockets isn’t there so we need to fallback gracefully. If all browser vendors don’t implement WebSockets in exactly the same way we’ll need to add workarounds in the same way we’ve done for years with JavaScript event handling and more recently the XmlHttpRequest object. If the standard API isn’t exactly what everybody wants, or the calls can be condensed by using a wrapper people won’t use the API directly and will actually do so via a library layer.

So, my opinion is: don’t care about the underlying communication layer, let a library deal with that for you. Let it chose the best way of communicating with the server so you can get on with building your real-time push application.