I'm glad it's not just me.
I swap between pbooks and ebooks regularly because I have lots of pbooks and use the library, but yesterday I borrowed a large hardback book from the library for the first time since getting my 505.
I was reading in bed and couldn't believe how heavy it was. Then as I got more tired I couldn't increase the size of the text either although I did look for the button
Had to switch to using my reader in the end. It's really inconvenient as I only have a week to read the book - just published so only available on short loan from the library, but as I'm only going to read it once it's not really worth buying an ebook. But it was just too heavy to read comfortably.
I used to prefer hardbacks, but they're far too big now!