I\'m curious what your solution is for high performance XML parsing on the iPhone is, given its limited amount of CPU power. I have reviewed the XML Performance App that App
You could always take a look at my replacement for NSXMLParser. It reads the XML data from a stream rather than keeping it all in memory, and passes it 1KB at a time into libxml (where NSXMLParser hands in everything in one go).
Source code is available on github and my writeup on the memory aspects are on my blog.