7.3 - Can make a User Inactive without re-assigning records
It is possible to make a User inactive without going through the 'delete' process which re-assigns records for the User. You are supposed to go to a User record and select More->Delete and then can select another User to re-assign records to.
However if you go to a User record you can do a Quick Edit on the Status field and change them to 'Inactive'. This bypasses the re-assigning process.