The videogame biz got a much-needed boost last week as Blizzard’s “World of Warcraft” expansion “Wrath of the Lich King” set a new worldwide single-day sales record for a PC game at more than 2.8 million units.Company didn’t release the game’s gross, but given a U.S. price of $40, it’s likely above $100 million. Expansion packs for “World of Warcraft” tend to get immediately devoured by the game’s huge and devoted fanbase of more than 11 million paying subscribers around the world. Previous record for single day sales of a PC game was last year’s expansion “The Burning Crusade,” which sold more than 2.5 million units on its first day. Given the core “Warcraft” game’s boffo growth in the past two years, though, “Lich King” sales do represent a decline in one way: In January of 2007, 31% of “Warcraft” subscribers bought “Burning Crusade” on its first day, compared to 25% for this year’s expansion. While it broke PC sales records, “Lich King” still didn’t come close to all-time videogame records set by console titles. Last year, Microsoft’s “Halo 3″ sold more than 2.5 million units its first day in the U.S. alone and much more than 2.8 million worldwide. “Grand Theft Auto IV” is also believed to have sold significantly more on its first day, though publisher Rockstar reported only that it sold 6 million-plus units in the first week. The videogame biz has seen its phenomenal growth rates slow this fall, though it’s still outperforming other media sectors. Publisher Activision Blizzard has to be pleased with “Lich King’s” growth over the last expansion, since one of its other huge franchises, “Guitar Hero,” has seen sales for its latest edition plummet from last year. In other videogame news, “Terminator” rights holder Halcyon has pacted with financier Equity Games Production and Warner Bros. on a tie-in to next summer’s movie. The “Terminator: Salvation” vidgame will be released in June along with the pic. Halcyon is overseeing production for the game at developer Grin Studios. Equity and its partner Evolved Games are financing the game, while Warner will distribute it worldwide.