From what I have read slight changes of temp are negligible and I get the impression that most of the more serious dslr users build up and use a dark library, I don't I just run a set after imaging.
But even this I have seen argued against with merit as continuous shooting does heat the sensor up and it should be given a chance to cool down properly before taking the next dark.
It starts getting too complicated for me anyway.
This article also has something to add and may be of some use to people...
http://www.cloudynights.com/item.php?item_id=2786