Jericho might be happy not to return to a company that has to feel eerily like WCW... some of the implications from recent interviews really point to a sense of disappointmnent with the WWE. And I personally don't want to see him come back again just to be lost in the chaos.
As for TNA... I would personally love to see it. There is an air of optimism and confidence in that product right now and someone like Jericho would be enough of a star to boost awareness while also being selfless enough to use that power to build newer stars. Will it happen? Hard to really say... TNA is different from the past few years so maybe he's actually looking at it now. And with the ease of scheduling around their dates, that might be appealing. But then there is the whole "I'm a WWE guy". Which then reminds us you can't really trust what he says a lot of the time. The guy works even when he doesn't have to