Beyond a certain threshold, you don't have a community, you have a series of sub-communities.
I work at Microsoft. Not for Microsoft; I'm a contractor. There is a culture of Microsoft FTEs (Full Time Employees, who have blue security badges), and a culture of contractors (who have orange security badges). This is explicitly noticed, and people refer to being hired for an FTE position as "blue badging". This contractor culture is subdivided into the "vendor" culture (people with v- at the beginning of their @microsoft.com email) and the "agency" culture (people with, you guessed it, a- at the beginning of their email). This difference is also explicitly noticed, and it is not uncommon to be asked "are you a v-dash or an a-dash?" once someone establishes that you are an orange badge. Each individual vendor or agency, in turn, has its own culture.
As you have no doubt gathered, this is a complete mess.
However, it only matters socially. Another person at Microsoft may care whether you have a blue or an orange badge, whether you are a v-dash or an a-dash, and which particular vendor or agency employs you. But that's the person, and their personal thought process - once you relate from a professional standpoint, it evaporates. The moment you walk into a meeting, nobody gives a flying leap. It is tremendously unlikely that you will be given great responsibility as a contractor, regardless of vendor or agency status, but what responsibility you are given is entirely yours. When you need the answer to a question, you can go to anyone that might be able to answer it. You can take the shuttle to the appropriate building, walk up to Steve Ballmer's office, and knock on the door if you feel like it. You'll get your arse handed to you if it's inappropriate, but you have the full and complete right to decide for yourself whether you think it is. Just don't be wrong. But right up till the very moment you turn out to be wrong, management will grease the wheels and clear the way and give you every opportunity to prove yourself right.
And that's what really, honestly, rocks about working here: you have the tools at your disposal to do whatever needs to be done. Not to mention, where else are you going to write code that might change the world? Even on the lowest levels, where you implement the most miniscule little trivial feature, where else can you write code that sits on over a billion desktops?
I love it here. I'd like nothing more than to work here for the rest of my career. Hell, if I didn't need the money, I'd work here for free.