Specifying the participants of a meeting can be quite an extensive task because you have to find each participant in the list and add him/her.
Usually people are working in groups and those groups tend to be more ore less static - sometimes a few people more or less. Therefore it would be really nice if there would be a possibility to "copy/clone" an existing meeting respectively using an old meeting as template. Then you would not have to edit the meeting from scratch...
Currently there is only one alternative (if the meeting to be copied lies in the past): re-schedule the meeting. This has the draw-back that all confirmations and declinations are not resetted if you re-schedule the meeting (and I have not found a way to reset all user confirmations and declinations of one meeting).