Joe -
Just in case you were wondering: the difference between your syntax (the so-called "simple case" syntax) and Andras' is that the "simple" version of the syntax assumes that the operator is =, so in your case - NULL=NULL, which by definition of NULL returns a result of UNKNOWN. So the case would fail.
The IS keyword isn't a comparision of a value, but a checking of a state instead.
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Your lack of planning does not constitute an emergency on my part...unless you're my manager...or a director and above...or a really loud-spoken end-user..All right - what was my emergency again?