I guess I was asking for it in my last blog post when I announced the courses and didn't comment on our exam plan. My inbox rapidly filled with really good questions with the basic context being "where is the exam?" so rather than address all of them individually let me give you the full picture.
We are working on a partner focused exam for BizTalk Server 2004. It will be part of the partner competency and will be delivered in March of 2005. One of my team members (Yumay) is working with the question writers marching forward on this right now with the folks from MS Learning.
So an exam is coming, it just not coming as quickly as I/you would have hoped.