Professor Hughes and others argue that thinking of the boomers in too-general terms could produce retirement policies that affect some boomers adversely. Stereotypes also mask the reality about the group, whose diversity reflects that of society, they say.
"I don't think that's a message that can be overemphasized," says Sarah Zapolsky, senior research adviser at AARP, which frequently researches boomer differences.
She is often put off by those who talk about the "tsunami" of boomers heading for retirement. "They made it sound like 77 million people are all going to retire in one day.... That's the clearest example of where the fallacy of thinking of the boomers as one unit comes in."
An obvious example of diversity among the boomers is their age range, which spans 19 years and means that while some boomers are grandparents, others are still getting kids into preschool. Some female boomers go to a website, Boomer WomenSpeak.com, to discuss their varied experiences.
"Just like any other generation, we've had different experiences based on the choices we've made," says the site's founder, Dotsie Bregel. "While there were plenty of [women] who climbed the corporate ladder, there were also women who chose to stay at home."
Marketers are already honing their pitches to try to reach particular segments of the boomers - such as those in their late 40s and early 50s whose kids are leaving the nest. But some findings in the Duke report, which is based on census data from 2000 and earlier, suggest more fine-tuning across cultural lines may be needed. Significant numbers of immigrants have joined the boomers, the analysis shows: Immigrants now make up 12 percent of early boomers (those born between 1946 and 1955) and 15 percent of late boomers (1956 to 1964).
While technically not part of the post-World War II baby boom in America, immigrants are nonetheless significant, argues Hughes. "Our point is that if you are concerned about people who are right now between 40 and 59, and you're concerned about what their impact on the US is going to be as they age, you need to consider the people who immigrated into that group."