No, there isn't any decorations in normal minecraft, I did see a BIG Christmas pack though, I don't remember who made it, but It had presents, Ornaments and such, The Yogscast uses it for their Christmas specials. Hopfully you will find it.
There is a thread right underneath your's (link) that has a bunch of designs for papercraft. My suggestion is that you make a bunch of them, get some string, and hang them on your Christmas tree.
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I am the bone of my sword
Steel is my body, and fire is my blood
I have created over a thousand blades
Unknown to death, Nor known to life
Have withstood pain to create many weapons
Yet, those hands will never hold anything
So as I pray, Unlimited Blade Works