While phsyically on the cruise ship your charges for voice are $2.49/min. Text = .50/send and .05/receive. As far as your Blackberry data, unfortunately it's not going to be available. (rough, I know)
While in port and docked you'll be able to use your VZW service as normal since it's all in Alaska. You'll just be roaming in an Extended Area so your services may be limited, i.e. spotty reception, slow data speeds.
What you want to do before leaving your home area is dial *228 and select Option 2 to update your Preferred Roaming List (PRL). This will ensure you have the latest network/tower information available on your device.
This information can be found here. Cruise Ship rates are near the middle of the page.
Hope this helps.