Sense? - No not really. I mean the sense part would make more sense if the users were the ones making the decision, based on pastoral leading and where the church as a whole is going. It's like a passenger on a plane going out and buying brand X tires to replace the planes brand Y tires that still work. That is assuming the pastor is not the one preparing the SSP, or now, MS for use each week, or is the one to actually use it. Perhaps a meeting with the pastor about what you already had, what upgrades could be made to existing system, and then discussing where he was hoping to go with the media presentations. Perhaps he was impressed with the content, not realizing that the presentation software part of the equation really to the end viewer was no different than what you had. I have seen a couple people's PowerPoint presentations that stood head and shoulders over another guy's Media Shout presentation. The big names in presentation software are all very capable, and, to the end viewer, do a very comparable job in a lot of aspects, so what is it that the pastor wants that MS can do that SSP can't?
Maybe you want to send him to a conference to check out an Edirol video presentation/editing package?