Well, I don't know that the first to reach 50 is such a big milestone -- most of the Western Conference is right there. The Spurs still have some tough games left between now and the end of the season -- 2 games with Utah, 1 with Phoenix and 1 with LA (hopefully a HEALTHY Laker squad).
The Lakers are really struggling with injury -- besides having Gasol, Bynum and Ariza, Odom struggled with sickness, Kobe's fingers and slightly sprained his ankle against the Warriors the other night and Fish suffered a bruised knee at the end of the Warriors game. I'm not trying to make excuses but I am hoping that the Lakers can get healthy for the 2nd to the last game of the season against the Spurs. It would be a GREAT game to watch.
Personally, I think TD belongs on the list with Magic, Bird and Russell because of HIS play -- not necessarily the play of his team. He definately had a lot to do with it but there have been some great players who haven't had the supporting cast that TD, Magic, Bird and Russell had. Hakeem is a great example -- the guy was phenomenal but didn't have the supporting cast around him to get it all done. Some of this definately has to do with skill but there HAS been a great deal of "luck" in who the teammates these players have had. Not discounting any of these guys accomplishments -- it's just hard to elevate some of these players above others simply because they had a better team to work with.