Innovation, we want innovation! That's the clarion call every year, isn't it? Reviewers often levy harsh criticisms on sequels and expansions that don't sufficiently change the standards set by their predecessors, and games that seem too obviously to be imitating the successful mechanics of other titles can get dragged through the mud. World of Warcraft game director Jeff Kaplan has a different perspective, though. When we spoke to him today, he said, "I don't want to undervalue innovation, but there's sometimes the wrong focus on innovation. I think you innovate when you need to... and I also think the best innovations are things that people overlook and don't even recognize as being innovative." Though WoW can be recognized as an innovator by introducing formulae years ago that brought new life into the MMO space, it's largely hailed today for having solid core mechanics, not for drastic self-reinvention. Blizzard's priority, Kaplan said, is to "execute on all systems well — whether they're innovative or not." So while Blizzard would rather be great than be brand-new, there is one key game mechanic that Kaplan thinks was revolutionary:"WoW 's rest system was the first of its kind, and people don't stop and think about its effects on people psychologically... [that there is] actually a bonus for coming back to the game, but playing for a long time is not a great thing," said Kaplan. "It's a subtle system, and displayed well. So although when people talk about WoW it's the last system on anyone's mind... every single MMO that's come out since WoW, they have all added that exact same system."