Here's the HTC G1 (a.k.a. Dream) sized up against the iPhone and HTC's Touch Pro: it's a kinda half-way house between them both. It's narrower, but taller and fatter—thanks to the slide-out keyboard—and lacks the deftly curved shape of the iPhone 3G, but it's a shade skinner than the Touch Pro. Looks it'd fit pretty comfortably in the palm. Check out the hands on to find out how it really feels.
DISCUSSION
Why would you show 2 of the phones in mm and one in inches?
116.84 x 54.864 x 15.748 G1
115 x 62.1 x 12.3 iPhone
102 x 51 x 18.1 Touch Pro
The iphone still has the smallest over all volume of the 3 by a good margin. The G1 has the largest by about 25% vs iphone.
Ill stick with the iPhone.