Alternate XamlWriter - better performance
Fritzenhammer points out a performance discrepancy in XamlWriter. It turns out that optimizations to the XamlWriter will not be ready for release. If you using XamlWriter a lot, then you might want to make use of the XamlWriter provide by Rob (WPF PM) on the msdn forumns. The usage is the same and the code can be tweaked as per the needs. The source file is attached.
FYI, you could read the original thread on the MSDN forum here