I think that's all just PR by Delta. How often do you think that Delta will ever get anywhere near $10K for voluntary bumping? I say it will never happen.Delta is first out of the gate, dramatically increasing the amount of money employees are authorized to offer for voluntary bumps, up to $2K for gate agents and almost $10K for supervisors, both well beyond what is required by the FAA for involuntary bumps.
http://time.com/money/4741108/delta-united-overbooked-flight-compensation-vouchers/
Imagine you're waiting for your flight and Delta starts by offering $400 (plus hotel and meals) for the first two people willing to be bumped to the next day. You can wait another day and want some money. But, it would be foolish for you to hold out for the full $10K, as someone will say yes for less. And an overbooked flight will always have people willing to be bumped for a lot less than $10K.
Look at it this way. When was the last time you were flying somewhere for something other than business and would not have taken $2000 to delay your flight for a day?