"To say that this UI is competitive with something like iPhone OS 3.1 (or 4 for that matter), or Palm's webOS is an understatement; in many ways it's superior to what Apple and Palm are offering."
Hard buttons are fine, but please, please don't make them touch-sensitive.
One thing to note though: it comes with a different mail application than Droid's, and that mail application silently bombs on self-signed SSLs. So, if you want to use SSL with your POP or IMAP account, in some cases you'll hit "Next" after setting up the server information, the mail program will go to "Verifying account information" for a bit, then come back to the same screen you were already on without any warnings.
Otherwise -- honestly, having used iPhones and an iPad recently, I found myself thinking that it still wasn't an iPhone killer, which is sad. I'd really like to see a solid iPhone killer on the market.
If you're looking to get one, I'd say the overall thing that blows me away is the performance in general. I've never used a more responsive phone- that includes the iphone. Sense UI, is better than I thought. In fact, I thought I was gonna flash it and put stock android on there, but now I think next time if I don't get an HTC, I might flash it and put sense on it.
Only downer is batter life- but that's an issue with most phones.
