Moving in Together: Giving grown children a home or vice versa

Hard times are here and there are lots of changes afoot: parents and their grown children are finding themselves more economically inter-dependent. Between 2000 and 2007, according to the U.S. Census, the number of parents living with an adult head of household increased by 67 percent. The numbers for 2008 and 2009 are bound to exceed those.
Sometimes, the move-in together is driven by the grown child's problem: loss of a job or a drastic cut in paycheck. (A growing number of companies are shaving the base salaries of employees by 5 percent--or imposing furloughs that take a salary down several pegs. Or the parents suffer the same layoff/salary decrease issue or their retirement savings are greatly diminished or gone.
Here's a story from the Chicago Tribune that catalogues some of the variations on this theme. One of the trends it takes note of is of parents moving to be physically closer to their children--even when the move means pulling up stakes and resettling in another city. They may settle in a place of their own or with their children. Many are doing so to provide babysitting--grandparents as nannies.