So, I've had an iPad for about a month and a half. Here are my impressions:
Overall, it's really nice. It fills the need for a little Internet-connected device that lets me watch video, read books, read online news, and browse the web. I used to keep my old 13-inch MacBook next to the couch for these purposes, but that MacBook is now in a closet. I've also put away my Sony Reader that I kept on the nightstand. I'm using it at work a lot more than I expected. My workstation has two monitors, but I find it handy to have programming documentation or technical books open on my iPad for reference. It essentially gives me a third monitor.
We take a lot of long car trips, and my wife really likes reading and web browsing with her 3G iPad in the passenger seat. It's a better experience than her MacBook Air.
The iPad is not a replacement for a laptop. When I need to do a lot of typing, or switch back and forth between applications, then I put down the iPad and pick up my laptop. But picking up a laptop is starting to seem like a chore. The iPad is not heavy, it's not hot, it doesn't have a whirring fan, it doesn't require me to assume an uncomfortable posture.
If you want a "computer," don't get an iPad: you'll be disappointed. Think of it more as a portable videogame console, or a Kindle on steroids. Saying that it is just a big iPhone is essentially correct, although many of the people who say that seemingly have no idea how useful a big iPhone could be.
The iPad is heavier than I expected. This is usually not a problem, but when playing any of those accelerometer-based games for an extended period, my arms get tired. On the plus side, I guess this gives me some exercise that I've been missing.
I use the Amazon Kindle app for iPad more than I use iBooks. I like the fact that with Kindle, I'm not locked in to Apple-only platforms. iBooks is prettier than the Kindle app, but the Kindle app is good enough. I need to stress here that I am talking about the Kindle application for iPad, not a Kindle device, which looks laughably archaic next to an iPad.
My only real complaint about the iPad is lack of multitasking, but that should be addressed in a few months with a new iPhone OS revision. (I have the iPhone OS 4 beta on my phone, and really, really miss the new features when using my iPad.)
In the month-and-a-half I've had the iPad, there has only been one instance where I went to a web page that didn't work due to lack of Flash. So that's not really a problem.
I've got the Apple iPad case. It is functional, but it is ugly.
My iPad has survived one fall from a countertop to the floor, without any ill effects.
I hope that some nice Android or Palm tablets appear soon. Competition and choice would be good, but right now, there is really no competitor to the iPad. It does what it does better than anything else can.
As a software developer, I'm excited by the new user-interface expectations being ushered in by the iPad. This will finally get us away from the 1984 Macintosh-style WIMP interfaces that we've been stuck with for so long. I don't like a lot of Apple's policies, but they are leading the way here, and other vendors will copy the good stuff, so we will all benefit.
Some must-try apps: