These days, I'm usually out of the house from 6:30am to 10:30pm at least four days per week, and usually six days per week. What with all that mobility, I can definitely see myself using an "in-between" device, especially since it supports e-books and movies on a screen of decent size.

(yes, you can watch movies and read e-books on an iphone, but I won't use a screen that size for those purposes. I already have to pay attention to my usage with mine so that I don't strain my eyes even with things as simple as twitter or email.)

My laptop's drawbacks in comparison to an ipad would be startup times and battery life. Even with the most conservative battery settings, I can only watch one movie, and only just, before i run out of juice. that being said, i have no experience with an ipad, so i don't know its battery life when watching movies.

theres things i would still use a laptop for rather than an in-between device, and that's my homework/word processing, and all of my personal finance stuff.