Very usual....all over the country.
I agree. Doesn't this happen all the time when new officials take office? They replace old staff with new staffers of their choice. My dad did it when he was elected D.A. Every new superintendent in the school district where I work does it. New head coaches do it. I'm not really seeing the problem here other than people are just looking for reasons to dislike a Bush.** It seems "mean" to do to the people who lose their jobs, but it's the nature of the beast and they surely know that when they get hired.
**There are other, legitimate reasons to be irritated with the Bushes.