I won't buy from iBooks because I want to read it on my eInk device and don't want to mess with removing the DRM (assuming its possible now). Plus I'm not happy with the alleged part Apple have had in bringing about agency pricing for books. (nothing against authors setting prices when selling direct as happens with apps, but I don't like publishers doing it).
Sony I try to avoid as much as possible because of their previous misdoings. I've a long list, but sadly you can't boycott everyone as a gadget nut, sony just happen to be in pole position (they've been there for the last few years
