Will Apple's new iPad upend the publishing industry?

I am on the fence about this issue but am going to say no. Maybe not for another few years. And iPad revolutionizing the published book market in a manner similar to what iPod did to music industry is unthinkable because as Sumitra pointed out there are players already in the market who are coexisting with the published books and have not been able to uproot it. Also when apple came up with ipods there was no other such significant player in the market to take the music world by storm so the ride was a little less bumpy for ipods.

Coming back to ipad and books, a lot of professionals like to read even the reports, weekly statuses and inventory reports in printed form even though soft copies are always available, let alone books. Also all the avid readers of my generation (in their 30's and everyone before us) grew up reading printed books and no matter how hard one tries, old habits die hard. Also this and the earlier generations are the ones with the purchasing power and are the decision makers for their kids whether to buy a Rs 20/50/100 book or a $600+ ipad to be used as a digital reader.

With the next generation however, born with laptops beside them and doing most of the reading online, it will be different, so till the time they come to the forefront to claim their spot in the sun and are decision makers, I would like to think that books are safe. (although we have seen the demise of newspapers in print atleast in the US).

I end with the Golden saying "Books are not meant as furniture, but nothing furnishes a home better than books" -- source unknown 

Earlier, digital music was a lot different. There wasn't that much content you could legally buy at a price that made sense and was easy to get onto our device. In the past 12 months, publishers are putting over 90% of their best sellers into e-book form. Very soon, authors and designers will move away from a static presentation of information into one that is multimedia-based with video and other media content. Also, the black-and-white Kindle, for example, does not offer the kind of digital palette that enables magazines to take advantage of picture-quality pages for content and advertising. Also, books are changing from being content sandwiched between two covers and organized by chapter. I don't think it will be easy for Apple to dominate the market of publishing industry.