put it this way...
if you are really very interested in flying... you should at least know some basic aviation news and some technical stuff even you have not flown before..
if you are intending to join a company and going for interview... i suppose you have to read up on the company exisiting structure and latest news... and attend the interview with proper dress sense... all shirt and tie... be humble... all these are meant to show respect to the interviewers...
in my humble opionion... no one really expects you to be a know-all if you have not fly before... but good aviation knowledge do at least protray that you have an interest..
do a search for some forums or websites...I took one week (some even more) to prepare for the interviews.
my 1st interview and 2nd interview was done in 1 week and waited one month before I was called up for medical...
good luck...