Here’s an interesting statistic: Consulting firm McKinsey & Co. projects that by 2010, half of all consumer spending in the United States will be generated by people age 50 or older.

It’s a reminder of just how important the Baby Boom generation has been to the U.S. economy over the past three or four decades. And now, just when you might think that power has shifted to younger generations, the McKinsey statistic helps us realize that Baby Boomers aren’t ready to leave the stage just yet.

In fact, they’re not even ready to leave center stage yet.

Here’s another interesting stat: The average age of creative personnel at ad agencies and related communications firms is … 28 years old. And the number of personnel over the age of 50? Fewer than 5%.

And therein lies the age-old, old-age disconnect.

Perhaps it isn’t surprising that ad agencies are stuffed with creative types who are mostly between the ages of 20 and 35. After all, that’s traditionally the demographic group most likely to buy and spend … and so the vast bulk of marketing dollars – traditional and emerging – are devoted to this segment (as true in the 1970s as it is today).

And of course, having a bunch of twenty-somethings spending time developing marketing pitches to other twenty-somethings makes perfect sense. It’s just that the 18-34 target is no longer where the bulk of the buying power is happening. That’s still happening with the Boomer group, whose average age as of 2009 happens to be 53.

Just how significant are “the oldsters” today? McKinsey’s statistics are telling. They include the finding that the over-50 population in the United States brings home nearly 2.5 times what the 18-34 group earns. Which makes it no surprise that the over-50 group represents more than 40% of all disposable income in the U.S.

And when you look at spending, the over-50 segment — which makes up only about 30% of total U.S. population — accounts for well over half of all packaged goods sales and three-fourths of all vacation dollar expenditures. These spendthrifts buy more than 50% of all the automobiles. They even spend significantly more than the average online shopper during the holidays – 3.5 times more, to be precise.

These are strong financial figures.

Now, consider for a moment to what degree ad creative personnel who are 20 years younger are going to really understand older consumers. Sure, they’re well-versed on the ever-growing interactive and social marketing tactics that are available today. But how likely is it that they’re actually able to craft compelling advertising and marketing messages to older consumers?

Undoubtedly, many will scoff at the very question. For one thing, these creatives grew up with Boomer parents.

But when you consider how many common, worn-out clichés one sees in the advertising that’s aimed at the over-50 set — online as well as off — it does make you wonder if the communications firms are putting their creative emphasis in the right hands!