I think this is really great new for all parties involved.
It's good for TNA because he seems committed to remaining with the organization, rather than simply using TNA as a holding pattern until a WWE return was in the works. He can be a pivotal component of their organization, if he can remain healthy, and be one of the guys they can build upon in their drive to crack the 1.5 ratings barrier.
It's OK for WWE because at this stage of the game they really don't need him, at least now they know where he stands so they won't have to even contemplate any suggestion of a Mr Kennedy return.
Personally it's great news for me as I am much more of a WWE fan than I am a TNA guy. I had no interest in seeing him return to the WWE, having a lot of hype and hooplah about it, have him receive a big push, only to injure himself again or end up in the doghouse with the WWE brass for whatever reason. I will enjoy watching him on occasion on iMPACT, but I won't miss him appearing on either brand of WWE television.
Win, win, win, as far as I'm concerned.