(Marc Stein) reports: NBA commissioner David Stern expressed cautious optimism this week that he can eventually broker a new labor agreement that pre-empts any threat of a work stoppage after the league’s current deal with its players expires in June 2011, telling that he and NBA Players Association chief Billy Hunter will meet as early as May or June for “substantive” talks… NBA owners have the right to extend the current collective bargaining agreement through the 2011-12 season, but are widely expected to reject that option either on or before the deadline of Dec. 15, 2010. There is growing dissatisfaction among many owners with issues such as contract lengths, average salary — roughly $5.4 million — and the 57 percent annual share of revenues guaranteed to the players during the most crippling worldwide economic slump in 80 years.