Just so no one is surprised...
2004 NFL Rule Changes
Rule changes have come out of the owner's meeting for the 2004 season:
* There will be an official 15-yard penalty for excessive celebrations and it is in addition to the fines that players already receive when they have "choreographed" or multi-player celebrations such as Joe Horn's phone call or Terrell Owens pompom dance last year. The yardage will be marked off from the spot of the previous play or, if it occurs after a touchdown, on the ensuing kickoff.
* Practice squads are now eight players, up from the previous five.
* Headcoaches or any player may now call a timeout (no more piling on the quarterback).
* A punt or missed field goal that is untouched by the receiving team is dead once it touches either the endzone or any player on the kicking team player in the endzone.
* Wide Receivers can now wear jersey numbers from numbers 10 through 19 even if jerseys in the range of 80's are still available.
* Teams will receive a third coaches challenge if the first two were successful challenges.
With the additional challenge allowed (providing the first two were successful) is what decidedly tipped the scales towards approving instant replay for the next five years.