I just passed exam 70-631, Configuring WSS. 3 down, 1 to go, (MOSS Config).
For a person who’s more of a developer than an IT person, I found the exam a little more difficult than the WSS and MOSS Development exams. A word to the wise: spend time studying NLB, DNS entries, SSL, ISA, and certificates. I personally found it very helpful to do some reading on those subjects. It’s good to get back to basics every once in a while. (My biggest complaint about the exam is that it seemed dated; there were questions specifc to MOM instead of SCOM, and Windows 2003 server instead of Widows 2008.)