At Carlson we are converting from our own CMS to a DreamWeaver/Contribute 
mash-up model. We have work with and look at many options and have 
decided that the client side stuff using jQuery or straight js leaves too much 
of a whole in terms Search Engine Opitimization and find/index ability. 

We are looking at http://aspnetrsstoolkit.codeplex.com/

This tool separates the query, sort, filter of the feed from the view 
(transformation into html via XSLT).

It is written for RSS and Atom feeds, but is open source and appears to be 
pretty easy to adapt to any REST style XML output.

We are flushing out the DreamWeaver/Contribute sites, by integrating Events 
feeds from events.umn.edu, UThink blog feeds for News and such, ASR course 
guide Web Service, and finally a couple of our own web service apps, for 
faulty profiles and such.

I'm sure their is something similar on the PHP, Rails, etc side but we run MS 
stuff for the most part over here at Carlson.