All I can think of when I see the "Will Defense" line is, if this IS the future of 4E, then finally we will have some sort of integrated mental combat. I mean, think about it: the psionics mental combat stuff always was tacked on, ignored, and generally poorly integrated (when it wasn't overpowered, that is). But with this, direct mental attacks work exactly the same as physical ones. You could have psionic classes that have "Mental BAB" and the ability to make a mental attack at will for 1d6 damage + Cha. It would be easy, and balanced with the physical warriors from Day One.