Mist would not receive any payments. I have not updated after 0.8.0. Is the reason because I have not done anything to choose which chain I will use?
Yes, you need to update to version 0.8.1 or later and then choose "Yes" to activate the chain, since that's where your (ETH) payments are.
(Old versions can only deal with "ETC" payments. If you choose to deal with "ETC" payments, be very careful about replay attacks that could cause you to lose ETH.)