Yes, among shall users (who are probably a minority anyway, and mostly English), What shall I read? Is rather an invitation for your friend to instruct you to read something. You could ask it of your tutor at university, or your boss at work. Shall is generally used when someone (or something) is determining the future, not recommending a future. You could also ask yourselfWhat shall I read? because you have the authority to determine your own future.