From the Store description we get this brief changelog:
Version 3.9.0.0 - yes these numbers actually mean something.
* Pretty much we just added more cards to the library - Fathers Day, World Cup. We will not be held responsible for the overwhelming love, kisses and smiles that can come from sending one our cards.
* Oh and some bug fixes a.k.a. we fixed the little things we had screwed up with the last update.
Here's the new topical content in action:
Ole Ola, indeed. Send your football mad mate a card from this app and make his day. Or something like that 8-)
In each case, pick the card template you want, add your own note, with full control over every aspect of the text font, then send it on its way using any of the sharing mechanisms in Windows Phone.
The developer does seem very responsive, I'm sure he'll be open to suggestions for future holidays and events. In the meantime, you can buy/update Sendtiment Cards here in the Store.