You are all overlooking something about Internet access on cruises: it is often much, much cheaper to use your laptop and wireless Internet on a cruise than it is to use their computers!
This is because they charge per minute that you are connected to the Internet. The per-minute charge itself is usually the same whether you're on the laptop or on their computers. But with the cruise line's computers,
you are always connected, even when you are composing e-mail. On your computer, you can compose offline, go online, click "send", and then go offline again! If you need to write a lot of e-mail from your cruise ship then this could save you a lot of money.
Now, not all ships have wireless access - most major ones do, but there are still some that don't. Most of the time it's only available in a number of "hot spots", though a few ships have ship-wide access (including in cabins).
This article (a previous incarnation of which I wrote, but I see it's been updated since then) offers a nice overview of what the major cruise lines offer.
As a freelance cruise writer I obviously cruise quite regularly and I
always bring my laptop with me. For me it is absolutely essential as I am not going to carry around 20GB of camera memory cards (though they are getting cheap enough now that I could!), not to mention that I'm cheap so it's important to me to save money by composing my e-mails off-line. Internet access from cruise ships is
expensive - and since it's charged by the minute, the slower it is, the more you use! (It's satellite, remember, so depending on where you are, it can be very fast, or it can be very slow or even nonexistent.)
Now, of course, not
everyone needs a laptop on a cruise. Many people don't. Many other people, like me, do. It really depends on what you want to do. To say, "you don't need a laptop on a cruise" is just silly, just as to say, "you couldn't possibly cruise without one" is also pretty silly! It really depends on what you want to do.
As for watching movies in-cabin, this I rarely ever do. But a lot of other people do! I am not a "cabin person" - I don't spend much time in there. But some people book huge suites (there's a reason they have them
!) and spend loads of time in their cabin. It's all down to personal taste - and budget. I will admit that I have never looked too closely to see what kind of jacks are on in-cabin televisions, but the TVs have certainly gotten bigger and nicer lately. Many major cruise lines are upgrading theirs and even adding DVD players and other goodies, not only in suites where they have been
de rigeur for years but even in standard cabins too.