Ok, it seems this isn't official yet, but the word on ye ol interwebs is that the first teaser for Man Of Steel will debut with TDKR. The teaser image is apparently from a magazine (still working on finding out which) and the blurb below popped up on a fan-run website for the movie - so don't take it as Gospel until we can confirm it..
"Warner Bros. will begin promoting its Zack Snyder-directed Superman reboot ‘Man of Steel,’ in a few days (a whole year before it’s June 14, 2013 release date). The studio had a similar strategy with ‘The Dark Knight Rises’. The teaser trailer for that film debuted July 18, 2011, almost a year to the day of its July 20, 2012 scheduled release date. The ‘Man of Steel’ teaser trailer is set to debut on or before July 20 (When The Dark Knight Rises arrives) with official movie stills to appear in movie magazines and online in the next few days!"
UPDATE: Yeah so it's not official I'm afraid. Apparently it was posted as pure speculation based on rumors, BUT, that doesn't mean a teaser won't debut - as we know it is very likely that it will - it just means we haven't had official word on it yet. Ah well! Hopefully we'll still get a few new images and what not soon.