Johnson is a target for Liverpool. Benitez hasn't much to spend and I believe a right back is high on his list of priorties.
I'd have him in a flash but if we were in for him he may prefer Liverpool as he'd probably be a guaranteed starter. He may want to join "the project" though :-) The world cup is around the corner remember so he needs regular playtime.
Keeping him, Zab and Richards happy next season could prove difficult unless we are fighting on numerous fronts ( cups, 4th place, europe etc )
IMO Micah's just had a blip this season and will return to his best sooner rather than later, although he needs to get out of the gym, take his head out of the clouds, and get his feet back on the ground.