Once Twitter announced that links, pictures and usernames would no longer count towards a tweet's 140-characters, it also started testing changes to how @ reply messages look. This week my account was included in that test, and as a longtime user, I don't think this change is a good one. As you can see from the screenshots, it puts more emphasis on accounts "real" names. that would be fine, except I've spent ~8 years getting used to the usernames of people I follow and commonly tweet to. Now, I can recognize some of those names faster than the person's "real" one, because this is Twitter, not Facebook.
Of course, Twitter would love to have Facebook's real name ties (and its ever growing user base), and maybe it thinks that phasing out the hacky @reply convention is a way to siphon people away from that other social network. Whatever the reason behind the move is, I don't like it.