Like yourselves I've had some emails. I'm not an O2 customer at present but ordered the Note 4 on the o2 deal from Mobiles.co.uk. Ordered Monday at around 1400 and have had 2 emails, the first is from Mobiles saying "Thank you for placing an order for the Samsung Galaxy Note 4. The handset is currently on pre-order and will be available after the official launch date of the. Once your order has been through the normal network credit checks we will email you with the status of your order along with an expected delivery date. As we are experiencing high level of calls and Live chat volumes there is no need to contact us, as all is in hand. In the meantime if you require further information you can always log into your My account by following this link; My Account with your email address and your Order ID number for the latest status about your new handset Yours Sincerely".
The second is an O2 email saying my userid has been created, 1p has also been debited from my bank debit card from Mobiles.co.uk.
Looks like their email might be incorrect or out of sync, from the O2 email it looks like the credit and network checks have been done. Wonder when we'll get the phone.