I must say, my criticism of the comparison of Clinton Fitch and of the comments here, is that they all only concern the "PDA"-capabilities.
However, in normal life many use a phone mostly for calling whether for business or personal.
Of course in formfactor, the the S740 wins handsdown as a phone.
I must say, my personal experience with the S740 and the Touch Pro confirms this (not surprising). Not having to use the touchscreen for dialing is a relieve.
Combined with its capabilities (qwerty keyboard, CPU, RAM, connectivity) it's the best compromise at the moment for business-use. In my experience, most emails that I must react to immediately are small and only text. Those are easily read on the small screen and the included qwerty keyboard is perfect for writing.
Of course I prefer a larger (touch)screen for reading/writing emails, surfing, watching foto's, etc., but that's simply impossible in such a compact device.
When I'm wearing a suit (I mostly do at work), I also carry my faithfull iPAQ hx4700 (really has everything except phone capability) because of its still tremendous 4" VGA-screen (I found the 2.8" of the Touch pro still too small). I still think it's the perfect size to check my calendar (Pocket Informant) and it actually is my daily navigation device (Navigon) in my car.
But if I don't wear a jacket, I can do everything easily with this fully packed compact (real) phone: S740.