The end of August is clearly the big time for C++/XML related fun -

• Apache have released version 2.8.0 of Xerces-C++
• Following that, version 1.1.0 of XQuilla is now available. XQuilla is an XQuery and XPath 2.0 library built on Xerces.
• Coincident with that is the release of another XQuery engine, which I didn't previously know about, called GCX from Saarland University Database Group. It sounds a bit researchy - the first streaming XQuery engine which implements active garbage collection, a novel buffer management strategy in which both static and dynamic analysis are exploited - but there it is.