Don't get too excited. Brett Favre has a history of making average receivers look like superstars. I don't think the Packers have had a real top receiver since Sterling Sharpe. But Favre is good enough to keep the passing game going regardless. The offensive scheme itself has been pretty good for that too.
Which makes him all the more better than Montana or Elway.
Other than Sharpe and perhaps Donald Driver now, Favre had to play with mediocre receivers who couldn't seperate themselves from bronze statues.