Howdy!

Sounds like in the beginning, a little diplomacy will go a long way. And flow charts! They're great.
But since I enjoy being devil's advocate....
Hopefully he didn't hire you with the idea that you'll be able to do your own thing apart from everyone else in the company, but if he did..... Since you'll probably be making a little more work for the others there - at least, they may see it that way because they'll have to change, and change is hard - you'll want to be as gracious and understanding as you can with everyone, educating them on why things are important instead of just telling them what they are supposed to be doing differently from now on.
Whether it's fair or right, it's your fault they're having to change. And if you don't get along, they could probably make it harder for you to do your work.

I would go through and try to put together some process flow charts for where and how you fit in to their current procedures, and what the responsibilities of the others are as they relate to you. Get full cooperation from the boss, and have as much of the major change communication come from him/her. That won't make it seem as bad that the "new guy" is messing everything up.

Of course, you may end up having a great bunch of co-workers who are excited about having you there and are willing to change to help make their work stand out more. Even if that's the case, the flow charts will still help.

Good luck!
Janell
(About to be getting my own new job here in the next few days...hopefully...though not in the SEO world...

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