Blizzard co-founder Frank Pearce recently spoke to VideoGamer.com about the possibility of a StarCraft MMO. In that exchange of words, it was revealed that Frank thought of the whole idea as an overwhelming thought. He cites the journey of working on World of Warcraft as a long an arduous one and that bringing about the same amount of content and quality for StarCraft would be, "A little scary."
While we know that some kind of MMO is in Blizzard's future, it sounds like if Frank had his way it wouldn't be StarCraft. However, by his own admission it's not entirely up to him as he adds, "When the StarCraft 2 team is done with StarCraft 2, a factor is what they want to work on next, because the development teams plays a big role in deciding what they're going to do." So once again, we really can't be sure of anything with Blizzard's next MMO. It could be something entirely new, or it could be one of their previous IPs. All we do know is that if it is StarCraft, Blizzard's Frank Pearce is probably going to consider an extended vacation. Something like one or nine years.