Via Ajaxian, XML.com has a good article titled Fixing AJAX: XmlHttpRequest Considered Harmful. The article states that the XMLHttpRequest object enables alot of the really cool stuff in today’s web applications, but asserts that the really cool stuff that can be done but is never talked about is using AJAX to consume third-party web services like those from Google, Yahoo and Flickr.
XMLHttpRequest has a basic security restriction prevents you from making XMLHttpRequests to any server except the server where your web page came from. To access third party web services, XMLHttpRequest needs to be fixed and those fixes are outlined as:
- Creating Application Proxies
- Using Apache Proxy
- Script tag hack with application proxy
