I am not sure I see the Dolphins signing him. Maybe they bring him in for a workout, but ultimately I don't see him being a Dolphin, at least not prior to training camp. Perhaps if there are some injuries or the WR corps looks really bad they could bring him in. However I think right now they are going to try and get their 5 or 6 receivers from the 12 guys they have on the roster right now.
Ochocinco is a diva receiver but really he is not a Marshall, Moss, Owens, Burress type distraction player. He would need to be managed and would probably be OK with a quarterback like Moore or Garrard throwing to him. The more curious situation would be if ends up having the rookie Tannehill throwing him passes. Tannehill is going to struggle early(if he starts the season), as do most rookie quarterbacks and a personality like Ochocinco might not be the best for the team. Less dangerous than a Marshall type player, but still could be dangerous.
I see some say that Miami wouldn't be interested at all since they just shipped Marshall out of town, but I am not sure I really see that connection. Marshall is one more off the field incident from probably being suspended for half a season or more. He has almost been murdered twice during his time in the NFL. Plus he absolutely destroys a quarterback mentally and was definitely not a fit for a team trying to build around a 1st round pick rookie. Ochocinco is more like Channing Crowder than Marshall.
If Ochocinco wasn't so old and coming off a very unproductive season I could see them signing him. Does he have anything left in the tank?