I think you're missing the point...
I for one have never used international dialing cards and similar services despite having family in Spain and Sweden, living in the UK and having friends all over the place. Why you ask? Because I don't want to have to dial a number and then input a code and then input the persons number to make the call... Id rather just select them in my adress book on my cell phone and call...
(And if someone has a service better than that they haven't marketed it very well)
I have Skype on my PDA but dont use it because of its sluggishness, and the need to sign on/off before being able to make a call.
So this feature lets me create a local number (that will be included in my stupidly large monthly minutes package anyway so as good as free for me) that is linked to an individual user (hence allows me to store it with that contact on my phone) at SkypeOut rates... Perfect!!!
Face it, the majority of Skype calls are to a fixed number of recipients, and preregistering them is not a big chore...
The pin issue... well if you want to call my mom you're more than welcome to, she'll talk your ear off... ;-) Basically since it goes to a specific recipient I'm not worried about the lack of pin protection on the number...