I'm huge NBA fan, but even I admit until the playoffs, its hard to watch the full game. Usually the game doesn't really begin until the 4th quarter. But if you are with group of friends or doing other stuff (such as browsing the internet) its perfect. You can casually watch until it hits the 4th quarter.
Betting wise, its the best sport to watch (I hate college sports). Even if your team is losing, you are never out of it. Its a game of runs and that emotional roallcoaster makes it exciting.