Although the firing process should be like ripping off a Band-Aid, it's still important to be respectful -- no one should be surprised they've been fired. Employees should be made aware of problems and given a chance to correct them. It's just good business sense.
When someone sends a mass email saying they are leaving, they often haven't thought things through. They are probably having an emotional reaction to what is likely a very emotional situation.
If the CBC has indeed fired an employee for private behaviour in the bedroom then Ghomeshi deserves the entire 50 million dollar settlement and those who made the decision at the CBC should immediately resign. If, on the other hand, there is a legitimate victim of a crime who is driven into hiding because people like a radio host, it will be a great miscarriage of justice by the Canadian public.
I have two key employees who have been with me for three years, both performing at a C+. I'd love to replace them, but they are both crucial positions and I just don't have the time to search for and train replacements. Should I fire them and suffer trying to find someone better or do I keep jogging along at a C average?