I've been counseled, by family & friends, for changing jobs every few years. The longest gig I ever held, after leaving the military in 1998, was for four years. During that four years though, there were numerous chanegs in the role and responsibilities. So, it was like getting a new one two years into it.

I'm contracting now and kinda dig it since the projects seem to have durations that fall in line with when I typically would get bored and begin to search for the next opportunity.