While there isn't a lot of information on their website, Electronic Arts has announced Battlefield Heroes, an MMO featuring the popular World War 2 milieu. Created by Dice, the team that made Battlefield 1942 and Battlefield 2, this will be EA's first attempt at a microtransaction- and advertising-based revenue model.
Judging by the look of what images do exist on their site, BH's graphics will likely appeal to certain players, but others might be put off by its cartoony style. Its being free-to-play, though, will no doubt make more willing to try it than not. However, after playing in all manner of fantastical, imaginative worlds, with characters of radically vast ranges of appearance and abilities, will people be interested in the thematically-limited (some might say 'pure') WWII genre?