If you want to check who the competition on your next pitch really is, don’t bother trying to coax it out of your client-to-be. Simply “Become a fan” of whatever your client is doing on facebook and voila, there are your usual suspects.
Caveat: This only works if you are “friends” with at least one of the guys from competing agencies or they have diligently joined a network showing their allegiance. OK, and if the brand you are suiting has thousands of fans it might also get a bit tiresome.