Desmond Hutton of Bloomberg news has written an article about Sony’s struggle to unseat Apple for the portable audio market in Japan. Sony entered the game very late — nearly three years after the iPod’s release — and has had lukewarm success to date. The company’s recently announced NetWalkman was less popular that three iPod models by the end of October, according to Gfk Marketing Services Japan, a Japanese research firm. “Sony was the pioneer with the Walkman,” said Alexander Shalash, who manages global technology stocks including Apple shares for Swissca Portfolio Management in Zurich. “This time they’re late. There are no alternatives to the iPod right now.”