Hello, I'm sorry to hear about your dissappointment. But as others have noted, the paired exchange program has some great benefits. As to the waiting time, you will find that there is no exact answer because there are too many variables that could make it hard for one of you to find the right match. Also, note that the "domino" and "daisy chain" extended pair donations that some people talk about are an extension of the simple 4-person "pair exchange," so that might add to the delay.
My mother is located in Massachusetts, so when we realized I could not donate to her because of our blood type, I looked into the New England Program for Paired Kidney Exchange (nepke.org). It took me a while to convince my mother to go along with the idea, but once we did, it was five months from stage zero until they had the full health work-up on me to get our data INTO the exchange database. (Sounds like you may be farther along in the evaluation process, so hopefully most of that delay will be behind you.) We entered the program and were part of the January 2008 computer run -- talk about suspense! With NEPKE, they run the computer program approximately once every 4-6 weeks to look for new viable pairs. None found in January.
(to be continued...is there a size limit for posts on this new board, or is my computer just acting up?)