I have had the Inspire for a few days and I thought I'd give my 2 cents. Just to give you some background, I have had dozens of smartphones. I benched my iPhone 4 for this phone.
Initially, my main concern was battery life. I'm happy to report that it's not an issue. While 1250 maH sounds like fail for an Android device with a 4.3" screen, it's obvious that the next gen Snapdragon is very good at keeping power consumption to a minimum. I unplugged the phone from it's charger this morning at 6 a.m. and at 10 p.m., I still had 30% battery. I had two lengthy calls and used the phone plenty to check e-mail and surf the web. I also streamed Slacker for a while. While I would feel more comfortable with a 1500 maH battery in the phone, the 1250 seems to be sufficient. I actually thought HTC was crazy when I originally read the specs.
Loving the new Sense. Not just the performance enhancements (it's fast), but the little things like the ability to skin and theme the device. Unlike Motoblur, Sense UI actually enhances Android. I have always felt this way, having had several HTC Android devices, but now I feel more so.
Screen is great. I don't like that you can see so many of the capacitive screen dots at times, but I can live with it. The screen is super responsive and very clear.
The Camera is actually really good. The main reason I held onto my iPhone 4 for so long was for the Camera. Every phone I have tried (I'm looking at you, Captivate) has let me down in the Camera department, but so far, I find the Inspire's Camera to be very sufficient. I love the interface and all of the effects, and the picture quality is excellent. Overall, the iPhone 4 is still slightly better, but HTC definitely put a good camera in this phone. It's the first phone since iPhone 4 that I actually have confidence in the picture quality (Samsung Focus was close) and wouldn't hesitate to use as a standalone camera. As some reviews have stated, the flash does make some night shots yellow, but this only appears to be true of fairly close-up shots.
Honestly, the only thing I wish this phone had was a Front Facing Camera. As little as I used it, it was just nice to know I had it on my iPhone 4. Still, I wouldn't trade this for an Atrix. I know that the phone will be more stable, functional, and I'll get an update to Android faster with HTC. Motorola soured me when I had my Droid X and proved that they shouldn't be allowed to mess with software.
Forget dual core. While the specs of the Atrix are impressive, I find this phone to be very responsive and smooth. It's clear that the next gen Snapdragon is more than sufficient for the task.
My only real wish with this phone is that I could uninstall ALL of the bloatware. I hate that about Android. WP7 lets you uninstall all apps and iPhone doesn't allow any in the first place. Android seems to be the whipping boy of carriers. I hate that the apps are ROM locked and that you have to root to get rid of them. This is especially true of the AT&T Navigator, which is pointless on Android in the first place. It's deeply integrated, too, so it shows up as an option when you click on a contact (use AT&T Navigator to get you to their address). I could hide these apps with Launcher Pro, but I shouldn't have to. AT&T disabling app side-loading is crap, too. We can always use side-load wonder machine (thank you Android Central), but disabling the feature is like taking a steaming dump on what Android is about (openness) to me.
Still, overall, I feel this is one of the best devices available on AT&T, and the only real Android option. Samsung needs to sort out their GPS issues (no, the software fix didn't resolve it. The issue is bad hardware) and Motorola (looking at you, Atrix) always manages to ruin perfectly good hardware with an encrypted bootloader and buggy software "enhancements". If you don't absolutely need a FFC, then this is your #1 Android choice on AT&T.