No, it wasn't scrapped. They just haven't released any images of it yet. They announced that set months ago, and until we hear otherwise, Gannon and Brooks will be on the way probably around November or December.
The current box set that's out is Favre and Urlacher. The next one, to be released next month, is McCaffrey and Thomas (who's based on Anthony Thomas, fyi).
Gannon and Brooks will probably be released around the time that NFL7 is hitting stores. After that, expect the announcement for the Super Bowl exclusives! My money is that they'll offer an Oiler's Eddie George and a Texan's Aaron Glenn.