Important bulletin to staff on the use of the words “yay,” “yeah,” and “yea”:
“Yay” is not in Merriam Webster* (our standard) but yes, everyone uses it so that should be the standard spelling.
“Yeah” is the informal version of Yes.
“Yea” (pronounced “yay”) is used when voting: yea or nay.
* But this is!
Merriam Webster 2007 Word of the Year
1. w00t (interjection): expressing joy (it could be after a triumph, or for no reason at all); similar in use to the word “yay”
When contacting authors et al., please don’t say Yay or w00t! w00t!, unless they’re very informal people, of course. This will go in the revised edition of the BMSIP [Berkshire Manual of Style for International Publishing] – w00t w00t!