I went back and reviewed Fedora Forbidden Items and saw nothing that applied to the situation with Firefox.  While I agree with the statement:  "The concerns raised are that the default configuration is an "opt-out" vs. "opt-in" model of Firefox issuing network calls back to Mozilla's servers, and Fedora's user base expects "opt-in" for these sorts of things."; I also expect that same user base would overwhelmingly prefer using Firefox (with ads), Chromium or Google Chrome over Epiphany, Midori or Konqueror.  

If you can disable the ads in Fedora's packaging, then by all means do so.  Changing default packages however is a big deal and IMO the only other browser that could match the universal compatibility and functionality of Mozilla Firefox is the Chromium project.  Chromium has yet to debut in the Fedora repositories... so that situation would have to be remedied first.