The move — widely expected to help boost music sales, and not entirely without purpose given tracks are now available in ful via straming music services and file-sharing networks — was being discussed in advance of the event as one of the key features for the iTunes 10 release. Seems the move was blocked by the National Music Publishers Association, who wouldn’t supply the agreements Apple required. Apple did have agreements with all four major labels, but publishers felt licensing issues still needed “smoothing out”. Jay Rosenthal, general counsel of NMPA apparently told CNet last week, “We believe that a license is necessary, and conversations must occur before song samples are extended.” Talks on the matter continue, so don’t be surprised to see longer song samples appear in due course — beginning in the US, no doubt, and perhaps percolating across the rest of the planet over time.