Could he be a regular catcher? Is he a viable backup candidate?
Paulino isn’t really good enough to be any more than a desperation option as a regular catcher; he’s a career .272/.324/.376 hitter in the majors, really slow, and adequate defensively. He’s had his chances to be a regular and hasn’t stuck. If he did fall into a job and got off to a hot start, he’s good enough so that it might be able to keep it for a season.
He’s a perfectly fine backup catcher, if he provides what you need. I don’t think he’s any better — or worse — than Chris Robinson, John Hester, or Luis Exposito.
Paulino was declared a free agent after 2012, and has not yet signed with anyone. I suspect he’ll sign closer to spring training, when teams realize that they need catching help.
UPDATE: Paulino signed with the Mariners.