If you have already spent a lot of time preparing for it, you might as well take it.
Otherwise I'd suggest that you try to get certified for something with a longer life span (i.e. the current SharePoint product range).
SP 2010 "FAQ" (mainly useful links):
http://wssv4faq.mindsharp.com/default.aspx
WSS3/MOSS FAQ (FAQ and Links)
http://wssv3faq.mindsharp.com/default.aspx
Both also have links to extensive book lists and to (free) on-line chapters