Is this an iPad killer? Not likely... is it going to be a good tablet? Yes. Will it take sales away from the iPad? Yes. Do I want it? No... and why is that? Because 7" isn't big enough, IMHO, and Samsung loves to bastardize OS's.
Being someone that owns a Nexus One and an iPad, I have no brand loyalty or OS loyalty for that matter. I just recently got my iPad for what it is, a large touchscreen that is great for web surfing, in class note taking, and messig around... plus it does a damn good job at being an MP3 player and video player. I got my Nexus One because I am a huge fan of Android, great smartphone OS, Apple could learn a thing or two (Android could learn a thing or two from Apple as well).
To be very honest, not going to sugar coat this at all, there is nowhere iOS surpasses Android by a long shot as many of you seem to act like it does here... does it have a better GUI thus scroll better? Yes... but as it stands, if I want to check my IM on my iPad, I have to close my browser, open up the IM client, check it, then close that and go back to browsing, and sometimes that means reloading the page I was on... with Android, I swype down, click on my notification, respond, then hit my back button and I am back to browsing... don't close anything, don't loose anything, totally seemless...
And of course iOS does things better than Android, like music and video playing, idiot proofing, web browsing is much more finger friendly and more complete (flash SUCKS on Android, don't believe anyone that says otherwise, they are full of CRAP if they say it works well, it DOES NOT WORK WELL!)
But as devices, not OS's, it is really hard to touch i/anything... the OS is always well polished and easy to use. The hardware is always top notch, good looking, and well put together. When you combine the two, it is very hard to beat, even with more bells and whistles.... this Samsung tab is going to be the same as most every Samsung "top end" product, will fall apart in a year or two, will have cripling Samsung UI tweaks, and while powerful, will be a one hit wonder in the ring.
Maybe when Google releases an Android tablet, or HTC makes one, we will see a real competitor to the iPad, but overall the OS and Hardware combo from Apple is better than anything else out there, or that I have seen in the works... and once 4.2 hits with multi-tasking, my few frustrations will be gone 100%.