I really agree about the storyboarding stuff - I've had a hard time getting into it. That said, I'm a very experienced iOS dev, and I use XIBs as extensively as possible. I started writing apps before Interface Builder supported iOS in the summer of 2008, and those projects are completely, utterly crippled by the fact that there are thousands of lines of code that create and position views. None of it can be easily redesigned for iPad or enhanced for the 4" display. It'd take forever.
Using XIBs is also great for universal apps. I can instantiate the same controller with one XIB on iPad and another XIB on iPhone, and the layouts can be tailored to the platforms. It's wonderful when a client comes to you asking for an iPad version of their app, and you can duplicate the XIBs, scale them up, resize controls and swap out assets and go home early.
One thing that does suck about XIBs is that they ALWAYS cause merge conflicts. That part sucks and really needs to be addressed (at this point, Apple would probably have to write a diff tool for XIBs!)
Using XIBs is also great for universal apps. I can instantiate the same controller with one XIB on iPad and another XIB on iPhone, and the layouts can be tailored to the platforms. It's wonderful when a client comes to you asking for an iPad version of their app, and you can duplicate the XIBs, scale them up, resize controls and swap out assets and go home early.
One thing that does suck about XIBs is that they ALWAYS cause merge conflicts. That part sucks and really needs to be addressed (at this point, Apple would probably have to write a diff tool for XIBs!)