Working in a Microsoft shop has been a lot better than I originally expected it to be five years ago. Obviously there are still the drawbacks with things like licensing costs and the operating system upgrades that seem to come with no significant advantage. However, we have just enough people that the costs are slightly lower than for a smaller operation, and we are able to take advantage of the features of products like Office, SharePoint, and SQL Server right out of the box without major undertakings.
While I try to imagine what it would be like in a bigger organization, I think it would be difficult to roll out services like we do currently. To me, it feels like there's a sweet spot in the size and culture of an organization where going all-Microsoft offers multiple advantages. I see something of a bell curve to represent a relationship between costs - both real and otherwise - and the fit of an organization for being a Microsoft shop.
In a small organization with 10 to 20 people, going significantly into the Microsoft product world is going to be prohibitively expensive unless the organization is trying to create some sort of competitive advantage focused based on the fact that they are a Microsoft shop. In a large organization with more than one hundred users, planning and implementation get a bigger role than in a smaller one. The idea here is not a new one in that smaller organizations are typically more agile than large ones. It seems like the organization where everybody knows everybody is going to be more able to quickly adopt and take advantage of the out-of-the-box integration Microsoft products make available. Since everyone knows everyone, news of good features or capabilities with a new product travel fast through the organization. In the size of organization where I currently work, I get the best of both these worlds - slightly bigger budgets but still an agile organization.
While I do enjoy the integrated Microsoft shop that we currently have, working in a business with less than 20 employees would be exciting if the culture fit it right. Could an organization like that really run well using platforms like thin clients and web-based services? Could Google Apps be a sufficient office productivity suite? Would using Facebook for collaboration enable teams to get work done? Perhaps I'll get a chance someday to test out these ideas.