Can XPS contend with PDF?

XPS is an xml-based format by microsoft for competing with Adobe's PDF. There was a big hype about this before it was about to come out. Having a save-as XPS format in Office 12 and the talk about the competition that it will give to PDF was the in-thing few months ago(as was every vista related stuff). Now this so called hype has taken its space way below the PDF seat. Apart from few blogs that were written in October- November the last year, now much information is available on first few pages of google. I couldn't even get a nice XPS viewer easily.
The white paper on XPS is available here. Only time will tell whether it will be able to contend with PDF or not.