With all of the "AJAX Hype" flying around these days, sometimes it's good to take a step back and look at it in terms of real cost to you and your applications - and that's what bjoern does in this latest post over on the thinkpgp.de blog.

While having a short discussion about AJAX and the ReST on our company's internal mailinglist Johann brought up some interesting questions about this AJAX hype: does it really work for "normal" web apps and how are the fixed costs for a HTTP request changing when using AJAX technology?

First of all, XMLHttpRequest has a problem: in InternetExplorer, it doesn't work without ActiveX. [...] Second, the fixed costs for a HTTP requests are changing: while AJAX technology is designed to load just the delta of the data, your application design has to be changed in order to keep the performance: don't include whole framework stuff while you receive a XMLHttpRequest that is only trying to receive three rows out of the database.

So, obviously, there are some "hidden" issues when it comes to AJAX that not everyone's addressing. It's good to see, though, that people are already starting to move out of the "wow, that's cool" phase and more into really assessing it in terms of how it can really help make a user's site experience all the better...