I work at a startup building apps ( http://zerography.com is currently live; hopefully more soon) to get custom printed stuff into people's hands for free, and think it's really great to see Google getting involved.

There's something extra special about getting a letter or package in the mail, and with the amount of time and cost involved in mailing something to friends and family, I'm really surprised I (and almost everyone else I know, too!) don't take advantage of things like this more.