My best friend had to upgrade his iPad v3 to the newest bestest one because he's been cutting off the spines of all his books and scanning them. And the old iPad couldn't handle his 600-some page full-colour textbook.

With all his books digital on his iPad, he can access any one he needs wherever he is. In his shop working on his car's engine? Pull up the manual. Waiting somewhere? Open a novel. Watch Netflix. Email me. Sure, he can do that with his LapMac, but it's nowhere near as convenient.
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Meanwhile, I was looking for an iPad (cheap) to download scanned piano music to. I play keyboard for a jazz/big band group. Some of the piano parts are eight, ten pages. That's been a huge hassle, and a nightmare for outdoor gigs. My friend gave me his "old" iPad. I currently have about 100 songs downloaded into ForScore. Now I'll be able to set my iPad on one single music stand (I've needed two for the pages), and with my Cicada PageFlip to turn pages I am all set to play!

Can I do this with any LapMac? No. Well, I suppose I could rotate the stand so it's horizontal, then put the LapMac on it. But the screen won't be vertical. And I'd be scared that any bump or wind gust will send the whole thing crashing. My iPad is OtterBox Defender-ed, and will be lashed onto the stand with OtterBox's spiffy utility latch thing. So someone knocks over the stand, the iPad is secured plus Defendered. And between sets, it's lots easier to take around with me than an Air. So in essence, no, a LapMac can't do for me what the iPad can.

But I'll grant, that's a pretty specific-needs situation.
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As for going iPad-only, Apple Themselves have told me that the iPad is not intended to replace a computer. It's not designed as a stand-alone device.

And I can say from experience that it is very hard if you don't have a Mac that'll talk with the iPad. My big brother gave our Mom an iPad v1--with which my old Tity-Mac would not/could not talk. Any changes, we had to wait for him to visit with his LapMac. Just a huge hassle, and happily dealt with when I finally upgraded. So while you can make do with just an iPad, it's not the happiest place to operate.

>'Kat