CR has issued a prediction for PMA 2009, based on the rumors that they have received. PMA starts in about 3 weeks at the beginning of March, although a release of something is expected next week on February 17th/18th.
CR doesn't think a Canon 700EX Speedlite will be released at PMA:
"I reported the possibility of a higher end flash from Canon. I think it's out there and more likely to be launched with a 1 series camera."
Again, this is their prediction based on rumors they have received.
Source: CR on 2/13/2009.