Oh, those guys.
It's true that copyright law hasn't effectively changed. However, that's not really the problem. In the past, creating entire copies of a piece of literature was pretty involved. If you tried to sell it, the authorities could potentially get ahold of it, and use it to find its source... you... and arrest you.
But with electronic files, you can more easily copy an entire work, and spread it globally. On the face of it, it's easy to see why people would panic at the thought, and seek to apply DRM to their products.
But, as we've discussed elsewhere, a fair business model limits the amount of "piracy" to a manageable level, and negates the need for DRM. Paper books are sold today at a price that is considered fair enough to prevent people from taking others' books and printing their own. E-books can be similarly priced to negate the need to steal them in the vast majority of the market.
Copyright law isn't really the issue... it's fine the way it is. It's the business model that needs to change to accommodate e-books.