Boxing is a great sport, but will always suffer from an overall lack of talent as it isn't a sport that a lot kids (especially in the states) grow up doing. It is a sport born from minorities and countries with less focus on the popular more accessible sports. Boxing is my favorite sport to watch, and I will never say it's dead, but it has declined sufficiently over the last 20 years. In my opinion, boxing needs these things to come alive again:
1. A dangerous, heavy hitting, charasmatic heavyweight that competes in a competitive heavyweight division.
2. A waspy white guy above 140lbs that the casual sports fan can relate to and rally behind.
These things will generate interest, as there will always be fighters willing to put themselves on the line in the ring, and that in itself will always be intriguing.
Unfortunately, the future looks bleak on those levels at this point. Boxing will always be the gentleman's sport, and all it takes is a huge fight to generate interest (like last weekend) but overall, Mayweather's style coupled with Pac's inability to cope probably shewed fans away a bit.