Very nicely written review! I remain impressed by HTC's build quality, although I haven't owned one myself (use a crackberry for work, and my wife uses an LG Optimus One). However, I've used this phone a bit and came away impressed (although I ended up playing Tower Defence most of the time.. addicting game that it is ;-)). Extremely well put together product, and you get the feeling that you are holding a solid well built and well engineered product.
In roughly this price range, the Dell Streak would also be a strong competitor. 5" display, Gorilla glass, 1GHz Snapdragon, 16GB inbuilt memory..
I also have to say that the Samsung Super AMOLED screen is probably the most stunning screen I've seen in a phone, iphone4 included. The colors and vividness are just too much! However, the phone itself feels a bit plasticky (rather, it is decent, but not as well built as its competitors), and doesn't give the same impression of being a premium product like the HTC. Plus, if I am not mistaken, it doesn't have an LED/Xenon flash, which is quite a shame for a product of its class... considering that camera phones are really poor at low light photography to begin with.
One other thing - Android 2.2 is quite neat! Even on an entry level phone like the Optimus One with a 600MHz, it runs quite smooth.. and Swype really is a must-have.