sorry for the delayed reply folks!
YESSS I DID GO TO THIS!
there was an ernie walkaround, everyone got (well the kids, i just demanded) a little coloring book that coincided with the count on sports dvd---- clearly the day was to promote the count on sports dvd. they played little commercials/trailers for the dvd too!
BUUUUTTTTT! even though it was sesame day........... IT WAS ALSO AMERICAN IDOL DAY TOO! which was cool b/c david cook made an appearance-- he threw the first pitch and led the 7th inning stretch. BUT IT WAS ALSO LAME, b/c it totally overshadowed SESAME DAY.
also, the game itself was pretty amazing. david wright hit a home run in the last inning to win the game. w00t! go mets!