I just returned from a cruise aboard Grandeur of the Seas and the cost for their "high speed" internet was $.50 a minute and the cost to use the stateroom phone was $7.95 per minute. The only time our cell phones worked was when we were in port in Florida or Baltimore...not in the Bahamas at all. The phone would say "extended service", but when we would dial it would all be in spanish and never went through.
You can get a connection for your laptop in the room. I forget exactly how much it was but I think it was around $100. It is functional and is roughly dial up speed. I was able to use my vpn for email and remote access but it was very slow. It was fine for regular chat and pop3 email access. Last I heard, they were working on wireless access on some ships. I don't know if they have implemented that yet. Phone access varies by carrier and by location so I would have him contact his cell provider with the itinerary. Between Verizon and Cingular (my wife had one and I had the other) the coverage is not bad but it does vary.