Dan has a post up at Future of Information Work on the question of whether Millennials are actually different in important ways from previous generations of young people (and young workers), or if they are just "troublesome" to employers because all 20-somethings inherently lack commitment and tend to take a short-term view of employment. This difference between "life stage" and "generation" is something I discuss in Generation Blend. Below is the comment I added to Dan's post.

I think there's some truth to the idea that life-stage has a lot to do with behavior in the workforce. GenXers in their 30s and 40s tend to show greater organizational loyatly and teamwork than they did in their 20s because they have kids and mortgages to pay. Many Boomers heading into their 60s aren't workaholics anymore as they look for ways to wind down their careers. Even if you correct for those changes, though, it seems to me that there are definite differences in the ways that the generations approach their various life-stages - usually by attempting to correct what they see are the errors of their parents and immediate elders. GenX parents tend to take more time off. Paternity leave has only become really popular in the last 10-12 years, and the parenting practices that were common in the 1970s would probably lead to a visit from Child Protective Services today. Silent Generation retirees are moving back to city centers to stay connected to cultural ammenities, while their immediate elder Veteran Generation seniors moved to retirement communities to play golf. Millennials I talk to tend to find the cynicism of GenXers depressing, and GenX insistence on independence lonely and intimidating.