Occasionally, there are questions for which one of the close voters is the Community ♦ user. When does this happen, and why? What is the difference between this and a deleted user?
For instance, one of the close-voters on this question is Community ♦.
This question was closed by "Mik" but his profile wasn't linked, which implies the user was deleted.
From this Meta question it is clear that Mik's profile is now deleted and hence his name is not linked to his profile.
Mysticial got it right: even though the question was just closed, the vote was cast over a year ago. Close votes are not deleted when the user who cast them is - instead, ownership is given to the Community user.
When a question is closed, the names of the voters who closed it are recorded in the post history. So questions closed after some voters have had their accounts removed will credit Community, while questions closed before voters have their accounts removed will attribute the original voters. This is the difference between the two examples you list.
Update 9th March 2015:
From now on, it may also appear that Community has voted to close a question as a duplicate to another. More information can be found here; rolling over the Community name will bring a tooltip saying that the OP agreed his/her question is a dupe.
