I'll be bringing my laptop with me in October...mainly to download photos so I don't run out of room on my memory stick. I have a tendency to go a little photo crazy DH still hasn't let me live down the $200 worth of photo processing I did on our last trip (before the age of digital cameras)
We won't be getting the internet daily because I believe its about $10 per night in the values. We'll get it just the day before we have to check in and get boarding passes with the airline for the trip home!
I'm sure you are aware, but just in case other posters aren't, thought I would add that you can always ask the front desk at your resort to print out your boarding passes for you (we flew SW and they did this no problem) so if that would be the only reason to bring a laptop or to pay the internet fee I would skip it.
We didn't bring ours, as it is a pain to haul onto the plane and I find that I am so immersed in the Disney experience when there that I don't want to be reminded of the real world at all, which e-mails, internet and even watching non-disney movies can do to me. We are also usually so busy and/or exhausted that it would never have gotten pulled out anyway.