“Once we get the seperation working properly, we can completely detach the development of front end from the application logic by first agreeing on an XML scheme to exchange data between those two.
By providing dummy XML to the guy doing the XHTML and CSS he can flesh everything out and then put it into an XSLT. Even before the application is built he can have finished everything… Then to get up and running, just the XSLT files, images and CSS need to be dropped in. Good to go.
By keeping the dataflow of the application logic stricly XML compliant we also have no problems using the same code for outputting a different version, to mobile devices, for example, OR to swap the data-source with an external web-service.
And did I mention that suddenly you can work with UTF-8 throughout the whole application and the XSLT automatically transforms it into the needed output format? You just need the right parser.
On top of all that, we are using a w3c technique and have the ability to render tree structures and stuff…”
XML as intermediate application layer
Source: http://www.contentwithstyle.co.uk