Continuing a 2005 slump for the vidgame biz compared with a strong 2004, Activision reported a 28% drop in revenue for the quarter ended Sept. 30 and slipped into the red.Company beat guidance, however, on a smaller and lower-profile slate of games than last year. Net loss was $13.2 million on revenue of $222.5 million. High-profile releases last quarter included “Ultimate Spider-Man” and “X-Men Legends 2.” Activision expects revenue of $790 million in the current holiday quarter and $1.48 billion for the fiscal year ending March 31. Guidance calls for net income in both to be 52¢ per share. Shares in Activision closed up 4% at $16.81 Wednesday before earnings were announced, but were down 3% in after-hours trading.