I think it's a great idea as well. Would you have a database that would have all of that info? Their birthdays, the kids bdays, furbaby bdays, etc. I think it would be hard to make it where you didn't know who it was for a year, though. What would you call the person for that whole time?
But changing the puppy pals up would be good; it would give each person a chance to get to know other people better. I like it!