iPhone vs. iPod Touch

In my relatively short gadget life, I've owned 2 Palm handhelds, a Treo 650, now 5 iPods, and the Blackberry Curve. In my current role as Director of Technology I'm constantly walking the line of "testing" versus "playing". Both are purposeful and appropriate, but I'm ever conscious of the money this sucks up and the time it takes away from my work and my family.
The iPhone is revolutionary by all accounts and is the precursor to how we will transition from the mechanized interfaces with technology to the organic - an ironic twist in the evolution of technology.
What makes me consider the iPod Touch is that it carries with it all that the iPhone has to offer minus the phone bit. If I'm happy with the Blackberry Curve as a phone and email device, do I consider an iPod Touch for the apps and PDA functions? (yes, that's right Steve Jobs said he wouldn't ever create a PDA and here we are!)
Ultimately I am headed toward an iPhone, maybe even as early as this week... we'll see what side of the fence I'm on in the morning.