The tough question is related to the solution, instead of being centered on the problem space. Where do we go from HTTP? What do we need? Most aplpications today are struggling to find a proper way to communicate with the server. Comet strategies provide bi-directional messaging between a client and a server. Internet Messaging Bus goes a step further, granting the following properties to the communication protocol:
- Guaranteed message delivery
- Guaranteed order of delivery
- Once and only once delivery
- Both client pull and server push data fetching models.
This seems to be the end of the AJAX hype, as it is know. That is, the XMLHttpRequest, by itself, doesn't grant all those nice things to any WebApp. However, the word seems to be catchy, and people seem to want to stick with it for a bit longer, and the current bet is a messaging protocol.