I'm not the most Christmassy person ever, however Smash's writing on this one is stunning. I can't imagine being able to write so well so large. That big red 'g' is spectacular. The colors go really well with the global wreath stamp, too. (Looks like it went through the sorting machine twice - I'm sure Smash will not appreciate the double barcode).
This is a really clever idea - the writing was done with the envelope opened up, then it was refolded and sealed again.