Advice with number 2!

My husband and I have an almost 6 year old son and in January we will have our 2nd son.  I am most excited to see him as a big brother.  But I also have a lot of concerns, will he feel that he's no longer #1?  And since he technically won't be, how do we balance it?  He is a very sweet, helpful and loving child, and yesterday I asked him if he was nervous about being a big brother and did he think he's going to be a good one. He told me he's scared because sometimes he's bad and he's afraid he will hurt the baby!  I told him no Jeremy you aren't bad, sometimes you don't do things we are happy about (like he stuck a peanut in his daddy's ear the other day and he couldn't get it out), but that's what little kids do in order to learn what's right from wrong.  I reassured him he will be the best big brother ever and how much his little brother will look up to him.