I think every club is entitled to celebrate, but some would argue as to there's a level that goes too far in the face of your opponent, unless you're lifting a major honour obviously.
Even at that, United were called out by rival fans for celebrating a mickey-mouse trophy, and I actually think the Arsenal celebrations today were more overboard than that.
I don't think I'd mind Arsenal winning the title as much if it wasn't for Arteta. OTT celebrations, whinging, kicking balls away, throwing the ball from opposition, never in his technical area, his cnut face - he's the most detestable and disrespectful manager in the PL by a long margin.
Having said that, I don't want City winning the 3 in a row as we did, and I don't think this is an Arsenal team that is primed to go on and dominate for a few seasons. This feels like just one of those seasons for them that is just written in the stars... 90+7 winner today, Jorginho with a the goal vs Villa last weekend, virtually no injuries all season... sometimes, lady luck is on your side.