I think we are getting there. More and more app Mac apps are being ported and are now available for iPad. For example, I am a decade-old veteran of word processor Mellel and bibliographic manager Bookends. Both are now available for iPad, with a good feature set. Together with the robust PDF support of a Goodreader or PDF Expert and all manner of cloud access, I am set for academic writing, especially with the recent mouse support. I can choose any bluetooth keyboard (which is better than any butterfly built in laptop one) and pair it up, and summing all weights up (including stands and more), I barely get to 700 grammes on a 11'' iPad. Its portrait mode is far more usable than a 12" Macbook for academic writing, and the keyboard decidedly better. Its a great library setup if one's main preoccupation is simply to write up and does not sit in a library to edit media or categorise images or PDFs.
The problem as I see it is that programmers have mostly adopted a 'phone' or 'mobile' mentality when designing for iPad. None of the core Microsoft apps, Word, Excel, powerpoint, make real use of the 12.9" real estate. I tested the 11" and 12.9" side by side for a week, and once you remove the obvious screen size difference, when it comes to single window operation, the difference between the two narrows considerably due to the apps not really seizing the opportunity to be different. Apps should look and operate differently according to the various sizes, and avoid being gimped because they are a tablet edition. I think Apple has laid the ground at the OS level for developers to up the ante, and they must now step up.