You know I find it strange that the close vote queue is so long, because if 10 users went there and did their 20 a day, then you would already have 200 done... So just a few more users and we could finish that queue... So how come the queue is still so big? Have we just not got enough users who are of high rep and want to?
It is so long because not enough users go there every day and cast enough close (or "leave open") votes to overcome the questions newly added to the queue. Although it is stagnated now, there was some times when the Close Queue grew to more than 1000 items until Luis Alvarado cleaned it up.
As I have access to the Moderation Tools I always go there and try to cast all my 50 close votes. But I'm not sure if it's worthy to spend time voting to close instead of answering questions.
Read also http://meta.askubuntu.com/questions/11592/ and links therein.