While sometimes the best team(s) are in the Eastern Conference, the Western Conference in general has been better for so long that it hardly merits mentioning at this point. It can just be assumed, until something dramatic changes.
This year is no different. While there are five or six teams in the West that we could easily see winning at least 50 games, in the East really only Miami seems certain to achieve 50+ wins. Sure, a team like Boston or Indiana could do it, but I wouldn't count on it. Nor am I optimistic that Brooklyn or New York will be as good as some people are saying.
Oklahoma City, San Antonio, the Lakers and the Clippers all have to be considered legitimate title contenders. Denver and Memphis also might end up with better records than anyone in the East, excluding Miami.
So let's not even consider the argument for parity this year. It's gonna take a lot of funky stuff to even consider making a claim like that. Eight of the top ten teams might be from the West.
The West is deeper, too. Teams that are potentially adequate (like New Orleans and Houston) probably won't ever even be seriously considered in the playoff hunt out West, while a potentially mediocre team like Cleveland could sniff the playoffs in the East. Obviously things change and are highly unpredictable, but the conference disparity seems to stay the same year after year.