The workload is just spread out across whoever is left and it will be expected to be completed. There will be no extra compensation given, just more stress and aggro.
I would not recommend that anyone put in extra hours to get the extra work done, if it's not done it's not done. Doing so will mean that the powers that be will expect you to continue putting in free extra hours and will not provide further resources to share the workload.
Sound advice, @kdm+1ti3PTjC.