What's in a tablet?

I ordered my Kindle Fire a month ago, and have been eagerly awaiting its arrival ever since. I carry my computer with me most of the time, so a 10 in. tablet seemed like a bit too much. When the Fire was announced, it sounded like the perfect solution for me. I love Amazon; I've had a Prime subscription for a year now, and I've had Kindles on and off for the past three or four years. And while everyone's been putting down the "Playbook" hardware, I like the sleek, understated look of it. 

Now that the Nook Tablet has been announced, I'm less sure. As far as books go, Amazon's Kindle service is clearly superior. However, the Netflix/Hulu integration is something that's really important to me in a tablet, and the additional internal storage is a nice plus. I'm still pretty confident that the Fire will give me everything I want in a tablet, but this just made me stop and think. What's really the most important thing in a tablet? Hardware, software, or content? And does the primary use (work or play) make a difference?