If i'm not wrong, East and West teams play against each other twice per season, home and away. So for instance the L.A. Lakers play the N.Y. Knicks twice every season.
I believe that now even the 1st round of the playoffs is best of 7.
There's no promotion or relegation, always the same teams (30).
Each division has 5 teams. 3 divisions per conference. 5 teams x 3 divisions x 2 conferences = 30 teams.
Standings are purely based on winning percentage. For instance, right now the leader of the western conference is Dallas, with 35W and 8L, with a 0.814 percentage. That's one of the things about basketball i love the most, you cant play for the tie, you either win or lose.
Some players to watch:
Kobe Bryant - L.A. Lakers
Dwayne Wade - Miami Heat
LeBron James - Cleveland Cavaliers
Carmelo Anthony - Denver Nuggets
Gilbert Arenas - Washington Wizards.
The All Star Game is on February 18th, be sure not to miss that.