Why are PayPal taking so long

Hiya!
Well, I revieved £490 for my iPhone 4S 64GB on Friday. I rang PayPal up and they said it'll be in on Saturday at 5 o'clock as their reviewing it, it wasn't in.
So I rang at 5:34 yesterday and they said it should be in by today at 10-11, it's not.
Are paypal making money of 'reviewing' my money? I've told them I need this urgently to pay rent and shopping. Does money not go through on weekends? As its not classed as a business day, will I get it Monday?

I've asked 'Louise', PayPal robot and all she gives me is that the money will be reviewed and ill get an email? Can someone help.

When they have large amounts of money involved and either the buyer or the seller has a short (or sordid ) history with paypal they wait until the bank or credit card company that the money came from assures them that it was not a fraudulent transaction. They also are waiting for the buyer to give positive feedback that the item was received in good working order.

They hold the funds for security reasons… Impossible to predict how long.
Seems strange that someone would pay that much for a 2nd hand iPhone… If you sold this to a total stranger via the Internet through a site like Craigslist, don't be surprised if you get scammed. The buyer could file a chargeback dispute, stating that the item was not as described.