Guess who I just heard from?  It's so cool, you'd never imagine, so let me just tell you:

His Holiness would like to thank all of you for the kind greetings you have sent on his 75th birthday. He is touched that so many people made the effort to offer their friendly wishes and, while he is unable to acknowledge each one individually, he would like to take this opportunity to express his appreciation.

With His Holiness's prayers and good wishes.