More good news: iceberg210 built on the Smile chords by Mr. Mediocre (posted this morning) by transposing them. This version works by capoing the guitar rather than retuning it. Both versions are awesome, so you can pick which method you like best.
Check out iceberg210's chords here, and then surf over to his Deviantart page. The more you play this song and the more you smile, the happier Pinkie Pie will be!
Thanks for sharing your musical talent, iceberg210!