Posting them on tumblr is ok, but I think a thread here to collect them all would be best! Personally, I want to see ALL the works, not just the one made for me, and they can be hard to track down on tumblr.
So I think everyone should post their finished work or a link to it here in this thread, saying "This is for X!"... well that's just my opinion!
I don't know the tumblr of my presentee. ;u; I guess I'll try to subtly find out...