Lack of library access is the Achilles's heel of the Kindle until someone wises up and cuts the red tape. The restrictive DRM used by Amazon to lock Kindles out of so many non-Amazonian book sources will eventually bite them in the butt, I hope. And as @tubemonkey points out, those of us who remove the DRM from our book
purchases are ethically challenged when we don't own the book, just borrow it. My current solution is to buy a second eReader that likes ePub format. A cheaper solution would be to simply read it on your computer, but this is uncomfortable for long periods of time and I find the tablets too heavy and awkward as well. So Amazon, having forced me to buy an alternate reader has also potentially lost sales, to me, of their eBook offerings, haven't they ... !
So far, I have found everything I have ever wanted either from online sources, or simply checking out the pBook from the library. We have a very good inter-library loan system (small town here) and can get virtually any book available by Overdrive (or other library eSources) in a week or less as a pBook. So while it is frustrating, it is not really a problem unless I simply refuse to hold a pBook in my hands.