I agree that it is not necessarily a "need" but more the "gotta have", LOL.
Be that as it may, it is definitely a tool to me in the fact that it is portable. I have brought it to take notes in place of toting my Macbook. I have a BT keyboard that converts to a netbook like experience. I am just as fine typing on the virtual keyboard, but when I am taking a several hour procession of notes, just from an ergonomic standpoint, I'll use the keyboard. The battery life is amazing. I use Docs to Go, sync to my laptop or desktop, and now have a copy of the document saved. If I ever get to go away again anytime soon, it will go with me for e-mail and surfing. It fits right into my purse.(I have a sectioned off purse and it slides right in). At night when I check my e-mail, my iPad is right in my nightstand, and I just take it out.
At work, I need the laptop for most things. I do however, bring my iPad to meetings and use it to bring up information to report, so actually it does help there, as I don't feel like bringing my laptop to it. A lot of my colleagues still bring things with pen and paper, and I don't like to.
So in my case, it's a darn good tool at both home and work. Oh, and I can also annotate work documents on it too without printing, like when a report is sent through e-mail. I highlight and notate what I need.