(Apart from quite possibly me, of course)
The iPad may indeed just be a big iPod touch, but almost everyone I've met who's heard of it (and most have) are positive. So here's my comprehensive list of things to say goodbye to.
1 The computer mouse. Of course. We'll clean the jam off the touch screen later, but everyone prefers touching to pointing.
2 Desktop computers in the home. Obviously. If the iPad covers wordprocessing, presentations and spreadsheets as well as Steve Jobs claims we won't even see desktop computers in many offices.
3 Amazon as a bookstore. Oh they'll still sell books alright. Premium versions, art books, signed celebrity editions, but their main focus will (has?) shift away from books. Their ebooks will probably continue, but say goodbye to...
4 Kindle reader. Why would anyone buy one now? They'll use their iPad as a digital photo frame when they're not stuck in a novel.
5 Microsoft in the home/small office. See item 3 for clarification. Unlike Apple Microsoft have never been able to develop anything other than their core product (Windows and Office).