I havent posted in a while because of work I am doing on another project but someone asked me about what comprises the \Winsxs store and it made me remember a really good blog posting done during the development of Win7 that describes where and how that space is consumed.  I thought it would be a good read for anyone who isnt already familiar with it.  It’s located on the engineering site here:

http://blogs.msdn.com/b/e7/archive/2008/11/19/disk-space.aspx

Enjoy.

--Joseph