It's so good, I've got two. One very early one with AMOLED in brown for personal use and one black one with sLCD for work. They are both running 2.2 now and I'm very happy with them.
I've bought them for my boss and another colleague, and we use them with Exchange accounts with no problems at all - this was a big worry when I first considered Android because without rock solid Exchange support you may as well give up.
I also recommended it to my brother in law, who only uses hotmail and got him connected.
Every user I've handed one of these phones to has been delighted with it, and so am I.
I don't know if HTC are going to see this, but I may as well list what I think they should do better next time
1. More battery. The single biggest drawback of the device.
2. AMOLED is better than sLCD, go beat on Samsung's door until they sell you some. Don't get me wrong, sLCD is OK, but AMOLED noticeably beats it for picture quality. They both suck in sunlight anyway so don't get excited about that.
3. More internal memory please and while you're at it go beat up the devs who still don't support installation to SD.
4. Bluetooth needs work, especially voice dialling and media streaming. BT is the only thing I've found that can force a Desire to reboot itself or worse, lock solid and need the battery to be removed before you regain control of the device.
5. Add a search function to the People widget/app thing. It is extremely annoying to have to scroll through 1500 contacts to find the one you want when using the phone.
5b. Why have People and Search people??
6. We need more documentation for the Company Directory feature of Exchange sync. I just don't know if I'm meant to be able to pull phone numbers from the Exchange Global Address List OTA or not. The option appears to be there.....
And that, since April 2010, is IT.
Fantastic phone, fantastic price. I just love these things and I'm waiting with great excitement to see what HTC do next. I hope that whatever it is, there's a Desire sized version of it (HD is too big, and not actually HD, natch).