Because sometimes, having 9 million subscribers just isn't enough.
It looks like Blizzard is gearing up to make another MMOG, because they're hiring a physics programmer for it. Let the speculation begin!
Blizzard Entertainment is currently seeking a highly talented game physics/collision programmer to help breathe life and realism into our next-generation MMO technologies. This is an exciting opportunity to envision and author innovative and cutting-edge physics and collision systems for today's most advanced technology. Interested applicants should possess superlative math skills and a discerning eye for detail. For more information on this position, please take a look at the job posting.
Check it out at Blizz's site.