I think it would be a good idea if MLB or teams offered a scorecard app for people to download. It might not be as cool as the old paper and pencil system, but it would be a great way to get the younger generations into keeping score. Let it have functionality to be able to import lineups from the team from wifi, allow fans to post to facebook/twitter, and even keep stats like "57% of fans scored it as a hit, 43% error," which could be posted at the end of the game (I wouldn't post that info in real time just to avoid fan unrest over the official scorer's decision).
I know they have unofficial scorecard apps out there, but having that good interact with the team's network would be cool and could promote people using their smartphones for good at the game rather than evil. Plus it's easier cleanup for certain fans whose wives bring them hot dogs with ketchup.