This is the main point that's gone missing on the "missing port whiners", that being: the iPad is the first of a new category of device which lies BETWEEN phones and notebooks/laptops.
Its OS is the iPhone OS, not OS X as such, which has some important human interface differences, its main attributes being self containment and portability.
The iPhone is nicely self contained and portable as I would expect a "phone" to be.
The iPad adds to that self containment and portability a large screen along with a touch interface, both of which enable a certain range of operability for apps designed to run on it.
The form factor coupled with the apps make for the uniqueness of the iPad. It isn't meant to be phone, and it isn't meant to be a notebook. Though Apple may relent at some point and add a forward facing camera for teleconferencing and the like, the iPad would make an awkward camera, as such, as it would be too large a box to handle for taking photos.
I think Apple is intentionally holding the line here against the inevitable grumblings of the unwashed masses, as the new device category created by the iPad and with the iPad as its sole member and guidon has had precious little chance to catch on or to be comprehended.
People need some time to get familiar with it and learn the types of things it's good at. My mother used to show me pictures of her as a child, some of them in her school with its blackboards and chalk, as well as individual "slates" which students used to write on with chalk to display their math problems and various word spellings, etc. Just as those primitive slates had their uses, so now does the iPad.
Apple will hopefully not kow tow to every request of every computer geek out there who may be oblivious to the genius of Apple's design intent for the iPad. Rather, the geeks will be left to quibble as they are wont to do over other gadgets and gew gaws which the competition may foist on them.
In the mean time, the iPad will proliferate broadly, finding happy homes everywhere in homes, schools, industry, business, institutions, churches, etc., doing the things people will learn that it does best and most likely never miss its silly SD card and USB connectors.