http://gizmodo.com/5458382/8-things-that-suck-about-the-ipad
Some complete dealbreakers for me are:
No HDMI Out
Want to watch those nice HD videos you downloaded from iTunes on your TV? Too damned bad! If you were truly loyal, you'd just buy an AppleTV already.
No Flash
No Flash is annoying but not a dealbreaker on the iPhone and iPod Touch. On something that's supposed to be closer to a netbook or laptop? It will leave huge, gaping holes in websites. I hope you don't care about streaming video! God knows not many casual internet users do. Oh wait, nevermind, they all do.
No Multitasking
This is a backbreaker. If this is supposed to be a replacement for netbooks, how can it possibly not have multitasking? Are you saying I can't listen to Pandora while writing a document? I can't have my Twitter app open at the same time as my browser? I can't have AIM open at the same time as my email? Are you kidding me? This alone guarantees that I will not buy this product.
A Closed App Ecosystem
The iPad only runs apps from the App Store. The same App Store that is notorious for banning apps for no real reason, such as Google Voice. Sure, netbooks might not have touchscreens, but you can install whatever software you'd like on them. Want to run a different browser on your iPad? Too bad!