I'm not sure if it's the same as the Diamond but we'll be going on the Caribbean Princess. We e-mailed them and asked them about the wireless connection and here's the response we got...
We have noted your inquiries pertaining to internet usage while onboard. Shipboard personnel has provided the following information. While you are able to bring your own laptop and access the internet using a wireless LAN card, this is not available in passenger staterooms. This is only accessible in the Main Atrium from decks 5, 6, and 7. Further, please be advised that as per Princess Cruises' company policy, if for any reason the passenger's wireless LAN card does not pick up the network onboard (assuming that the network is available), shipboard personnel are not authorized to make any attempts to make configuration changes to a passenger's laptop. The wireless service is charged at the same price as the Internet Cafe, USD $ .35 per minute. Passengers are able to buy half hour vouchers for USD $10.50 from the Passenger Services Desk on deck 6.
Additionally, we need to advise that some internet sites are blocked due to Princess Cruises' security policy. Without knowing the site that you will be connecting to in advance, we are unable to guarantee that you will be able to connect while onboard. As you are wanting to connect to your work email account, please ensure that this is working and available before boarding the vessel. While onboard, they will only provide a "connection" to the internet. The passenger will be responsible for access to internet email.
