In one of PewDiePies latest videos (which can be seen below) the issue of YouTube comments is again addressed. I think most people agree that this is something that seriously needs fixing. He clearly realizes that what says will be heard by the powers at be at YouTube however whether anything is done about this everlasting problem is another story. Valid points about how anyone can use the name PewDiePie on their accounts or indeed the names of any youtuber to post links to ad websites. This is clearly a big issue as many youtubers use there comments to gauge responses so no one wants to have to filter through spam links to find genuine responses. In the video it is highlighted that there is people making quite a bit of money off posting links from accounts which are made to look like big youtubers, it is both dishonest and crafty at the same time.
All in all the majority of people would agree that preventing anyone from using the names of youtubers and preventing links from being posted in the comments would go a long way to solving this matter. A slightly more tricky solution would be to implement moderators in the same way Twitch utilizes them.