PC - Yes
360/PS3 - Probably not.
If any of you have ever messed around with the Cryengine 2: Sandbox 2, you know how many features that program packs. I doubt that they would be able to optomise the interface and streamline the functions enough for a Joystick/Button layout. There's just too many functions. If you have looked at some of the screenshots for Sandbox 3, it has the same layout and interface, just more functions. (Making it even harder to port to consoles.) However, the fact that they have released Screenshots and videos of the Sandbox 3 editor in action on major videos makes me assume that the PC gamers will definitely see the Sandbox 3 editor on PC. I could be wrong, but I doubt Crytek would want to leave PC gamers in the dark without an editor, when some pretty fantastic user-made maps came out of it on Crysis 1/Wars (all DLC-Related cynicism aside).