Minecraft is thinking of name changes as said in 1.7.9 name changes can be good in some ways and bad in this way:

You could be a very good player well known and then you change your name and nobody knows you that you used to be a good player.

Good:

You could be hated by the whole Minecraft and name changing fixes it (Just my opionion) 

Another Bad:

Everyone could be changing their name and then you could have no friends anymore that you remeber changed their name.
 If you change your name you could be lonley! 

_---_ Mojang may not add Name Changing in 1.8 it may take a while cause of there other things to be added _--_

Thank you.