Sure, but it wouldn't be mobile like a laptop in that case, as I'd have to be tethered to a desk. I don't even have a desk in my condo, when I work at home I do it on the couch in front of the TV. I spend so much time at my desk in my office, I can't bear to do it at home.
Maybe a laptop with a detachable screen could work if someone gets it right and makes both a fully functional laptop (not an underpowered netbook which is useless for my needs) and makes the screen/tablet have it's own OS that's as intuitive or better than the iPad's etc.
I don't see that really happening as it will be tough to get a company to get both parts right, have good form factor for the tablet etc.
Besides, my work provides my office desktop and laptop for working at home, so I'll always have those so I have no issue buying a tablet to supplement those since I'll probably never have to buy a personal laptop.