Some Boomers will be pulling money out of their IRAs & 401ks, but they will get eaten alive by taxes if they take all the money out within a few years...so they'll have to play with the numbers and hope they guess correctly. There are two other factors to consider:
1. Will Boomers pull all their money out and bite the bullet if they think that congress (or executive orders) might raise the tax rate?
2. Will Boomers pull all their money out due to fear of inflation?
Most of the other Boomers don't have enough money in their savings or IRAs to make much difference. Still, after all the hits that Boomers have taken recently, I wouldn't expect many of them to be heavily invested in stocks today....mostly just the gamblers trying to make up for losses.