Boxing is still big. On a global scale. It's just not popular in the US. On a global scale, it's probably in the top 5 popular sports, second only to soccer. Also, the only reason there were 90,000 people at that fight was because TVs weren't accessible to the general public. If it was, there would have been far less people at the fight.
If you think Boxing is still in the forefront, go out in the street and ask the first ten guys you meet to name 3 world champs.
In the UK its dead, boxing is a circus over here a tv event featuring Haye/Khan thats about it,the average man in the street could not tell you the name of the Heavyweight Champion. That's boxing's birth place, and the country with the greatest store of memories of the noble art ,indifferent to it. Boxing is a poor relation to other sports ,and has been for many years. Look how many newpapers have columns devoted to it? When I was a kid EVERY paper had its own boxing writer. Today you have a job finding out the results of a fight, if you rely on the tabloids. Face facts.
A little before my time, but boxing was once front page news, and not just championship fights either. The only sport that rivaled it in the States was baseball.