I have an excel sheet that recalc very fast under 2003, under 2007 it never
finish. The formulat that causes the problem is an array sum of a sumif...
What I'm trying to do is sum a column if the values are equal to a range of
othe values... A typical use would be:

={sum(sumif($A:$A, G5:K5, $B:$B))}

what this does under 2003 is sums the values in column B if what's in column
A equals the contents of G5, H5, I5, J5, or K5.

As I understand it the sumif creates an array of the sumif's and then the
array sum sums all those values.

In 2003 blazingly fast, under 2007 even with one such formula it never
completes. If interested I have an example sheeet.