luxurysem - 3:00 pm on Feb 1, 2006 (gmt 0) I'll post the answer once(if) I get a reply.
Just an update on the situation. The problem still persists despite Yahoo claiming that they've isolated it to the west coast mainly.
From what I've been told, it's a server syncronization issue. The servers are not all in sync with the DTC and each other so even if you bid for pos. 1 let's say, depending on which server is displaying the search results and your ad, the position will be different each time the term is searched.
I'm still trying to get more info on this problem because even if you bid for pos. 3 you might sometimes appear in pos. 1. In this case would you have to pay for pos. 1 or pos. 3?
I'll post the answer once(if) I get a reply.