We've written a bit about the Cartoon Network MMO FusionFall of late, which enjoys a great deal of popularity with younger MMO gamers. Now it looks like two other cartoons will be coming to the MMO space: Tom and Jerry and Ben 10. Tom and Jerry is going massively multiplayer (for Asia in 2010) through TurnOut Ventures Limited, a joint venture between Turner Entertainment Holdings Asia Pacific Limited and Outblaze Investments Limited.
Hong Kong-based Typhoon Games (who are developing Hello Kitty Online) is developing the Tom and Jerry MMO. A look at the TurnOut Ventures product page also shows they're working on Ben 10 Omniverse. Both massively multiplayer titles are being built on the Unity game engine, for PC and Mac compatibility. There's no announcement at this time for North American or European releases of either title.