I've noticed I still have some hits that after a week are still pending. It seems like there should be a time limit for the hits to be approved. We only have a short time to complete a hit it seems like it would be fair to have it go the other way too.
The HITs which are pending for more than 30 [or 31 days] get auto-approved. I was furnished this info by mturk on inquiring about it.
I'm close! I got 5 pending from Jan 21, today is Feb 13. Another week and they get auto approved. FYI they are from requestor "Amazon Requester Inc." Title: "Are these items different?" Seriously, what takes so long, they're only worth $0.01 each.