He's no longer insta-ban unless someone is extremely good with him.
1.) He's not boring, rather he can really **** over players by sticking to them/being a disruption. Most people would rather not think outside of the 4-top/1-bot meta, and champions like Rammus force you to think harder if a skilled one can tank, taunt, and POOTERSS around all at once. I just got cursed out for it yesterday Veni, right before my match with you, lol. He's boring when people can't faceroll (guess who stated he was? A Jayce player, and a Pantheon)
2.)If people are smart, the ideal thing to do is focus him, especially early game. If he starts building resistances, well focus the damage dealers he's protecting or get LW/Void Staff (Because I can't stress enough how derpish people are when they continue to build damage and very little armor penetration)
3.) Rammus can be dealt with if he decides to go backdooring. All it requires is a little more map awareness.
Essentially, Rammus is only a pubstomping champ. He's a real feat to play once you take on stronger peeps, and if you're good with him in tourneys, they will ban him. Have no fear.