Much as I love my e-readers, paper tech books and other textbooks are really still the only way to go simply because you can't easily flip back and forth between pages to cross-reference things or find specific information by flipping to a chapter quickly.
For fiction and any other type of linear reading material though, e-readers have been a godsend.
I disagree. Navigation non-linearly through electronic versions of texts is much easier than having to fan through the pages to look for that one phrase or code snippet you saw 3 months ago. Search and bookmarks...I've seen this in PDFs for years though I don't have much experience working with the newer e-book specific formats.
You'd be amazed how quickly you can find something in a book (or in a few cases for me, a blueprint) when you can just hit F3 or ctrl-f and search for it.
If you know precisely what you're looking for, I would agree that direct search is great; heaven knows I've wished there was a way to grep a book often enough.
However, I often find myself in situations where I don't know precisely the term to search for and am simply browsing to see if there is some information applicable to the problem I'm attempting to solve. That's where the ability to flip rapidly back and forth shines.
Tech books are the only thing I read on paper. I love free tech books, but honestly I'd rather pay to get the physical copy, just for ease of reference. The only time I enjoy digital copies of technical books is when copy and paste works, which it doesn't on Kindle books.
For fiction and any other type of linear reading material though, e-readers have been a godsend.