There are some inconsistencies in the Dashboard widgets used for editing existing stuff.
After editing an existing post from the Manage/Posts the button for republishing reads "Save" which seems perfectly clear.
When you edit a comment from Manage/Comments, the republishing button reads "Edit Comment" which seems less clear, as this is what you just done.
It may seem like a cosmetic question, but consistency is essential, although in this case not high priority.