I say mee-bah. That's how I've always said it since I first discovered the site. I might try converting myself to say mih-bah, or possibly just start saying meebs. Haha. I like that. :)
@ never quite awake. Agree with you. Rules of the English language dictate it would be pronounced Mih-bah because there is nothing to give that 'i' and long 'e' sound within the word.
"M", then "ibb" as in "nibble", and then "a" as in "Nora".
I would sort of understand why people might pronounce it "mee-ba", if it were spelt "Miba". But even then I'd probably be inclined to rhyme it with "fibre" in that case.