meh: An expression of indifference or boredom, or an adjective meaning mediocre or boring. Meh recently made it into a British dictionary — you can read the story here.
Bob: "You wanna go out tonight?"
Jill: "Meh."
Bob: "How about we stay in and order a pizza?"
Jill: "Meh."
Bob: "How about we drop our pants and run around the house singing songs from Wicked?"
Jill: "Hey, let's go out to eat!"
or
"On a scale of ugh! to oooooh!, wedding receptions are meh."