New Post: Is it possible to use a variable to store the value pairs for a SPServices.UpdateListItems call?

Sorry, I didn't see the quotes around the definition of the ValuePairs array.

Of course the variable needs to be an array of arrays not a string.
To understand better:

var valuePairs = [];;

//add Title
valuePairs.push(["Title", "This is the title"]);

//add FieldA
valuePairs.push(["FieldA", "This is the field A"]);

Regards
Michal