EDIT: 4 hrs 30mins after request, BTC withdrawal has been received in my wallet.
You lucky. Receiving on the same date is quite fast
Are you implying that Gox is systematically delaying Bitcoin withdrawals?
That would be an intentional delay, as there are no technical limitations (except for rare cold storage visits) for broadcasting transactions immediately.
(I just ordered a BTC withdrawal and indeed I'm not seeing the transaction yet.)
For BTC withdrawals, I don't think it is intentional. Though there are no technical limitation once they send the transaction to the network, there seems to be technical issues and financial issues within them. Apart from exchange, if we consider it as wallet, they could net the transaction or hold for cost saving, verification purpose or so, however it is not going straight through due to their internal scheme. Once this kind of congestion happens, the situation is getting worse dramatically under 24-7 operation.