Dave Jilk passed on this article by Dominic Humphries explaining why Linux is Not Windows. The analogy that starts off the article is perfect:
Linux <=> Windows is like Motorbikes <=> Cars: Both are vehicles that get you from A to B via the roads. But they’re different shapes, different sizes, have different controls, and they work in fundamentally different ways. They are not freely interchangeable. They have different uses and different strengths & weaknesses, and you should pick whichever is appropriate, not pick one and expect it to do everything that the other can do.
This is not a screed on why Windows sucks, or why Linux is great. Rather, it’s a very thoughtful article on the differences between the two.