Looks like the USA Today article was the sign we were looking for as the MichaelBay.com Facebook page has confirmed (along with Apple Trailers) that the new theatrical trailer for Transformers: Age of Extinction will be released on Thursday, May 15 No exact time frame is provided. at Midnight Pacific time / 3AM Eastern time. Last month the UK ratings board indicated this trailer would be 2 minutes, 25 seconds long. As for watching it on the big screen, safe to assume it is attached to Godzilla but as usual mileage will vary on that as theaters can choose to do with the trailer what they wish. Thanks to John W. for heads-up.

Update: Now have an exact time via MichaelBay.com:

‘Transformers 4' Theatrical Trailer Debuts at Apple.com on May 15 12AM [PT\3AM ET]

Be sure to check Apple Trailers on midnight May 15 for the Transformers 4: Age Of Extinction theatrical trailer.

http://trailers.apple.com/trailers/paramount/transformersageofextinction/