Hardware = Good. Software = Bad
When I first got my Kindle Fire, I was worried that I'd bought a pile of junk. It was so unresponsive to prods.
Then I swapped out some of the stock software for alternatives. E.g. I loaded up Dolphin HD web browser. I couldn't believe the difference! Nearly every click worked perfectly in Dolphin! In the Amazon Silk browser I'd have to click several times before it finally registered it.
The same thing goes for most of the other Amazon apps. I dunno what they've done wrong but it's a big cock. I'm glad they're going to fix it.
Aside from that, I've really got no other major gripes with the Kindle Fire. You can use a microphone with some apps (inline headphone type). I got it working with an audio recorder but most apps can't use the mic. I'd like to see them add proper support for it so we can use Skype. It's half way there so it shouldn't be hard for them to do it!
Also the onboard chip that handles Wifi also appears to have bluetooth and FM built in. Wouldn't Not overly bothered about them getting enabled but it wouldn't hurt. May allow us to hook up a bluetooth GPS and run TomTom or something.
TBH I'm looking forward to those geniuses over at cyanogenmod and xda-developers releasing the ICS rom for Kindle Fire so I can just run regular Android 4.0 without any of the Amazon stuff. I'm not in the US so there's no benefit for me anyway. They're nuts if they think their UI changes make android look better than other third party apps like Go Launcher.