As a physical keyboard fan the Dream was awesome. Sure, the trackball was wonky, the multitouch sensor was limited and the screen resolution and RAM was very low by today's standards but it was a great start. And given that it was hackable (in more than one way, remember the hilarious telnetd thing?) and had a keyboard it was 100x better than the iphone. Connectbot was the absolute killer app for me. I also fondly remember the nice tactile navigation buttons, it's been all downhill since then on that front.
I always thought that the BB-like prototype looked pretty neat too, if the keyboard and button bar could have been made more compact to make more space for the screen.
Now all the phones are exactly the same, there is very little experimentation or innovation except for small players like the fxtec pro (waiting for mine to ship)