I've polled my friends about this, and our group is a about 50/50. Some of us when looking at comments never read the usernames, we just completely skip over it. And some alway do - the next is right there of course you'd read it!

It seems like an interesting dichotomy - I didn't see any obvious correlation between other traits in my informal survey but I am very curious to see if there is some set of personality traits that correlates with reading vs ignoring user names.