jinitron, the @ only started within the last year, obviously in preparation for this 'system' so most comments on old clips don't even have it, if you have the patience to look through pages and pages for the original a la Twitter. Even then, you don't know which comment to attach it to if the member has made more than one.
I don't know any of the technicalities but the replies indented underneath the original made it very easy to see who was replying to someone else. It worked even if they were months and perhaps years apart and although I remember a paging problem on massively commented pages like the Susan Boyle clips, I never came across an issue with the reply system.
Chronological order is what we have now and it makes nonsense, especially on the older clips. I can't understand some of my own comments myself and on one clip I'm even 'agreeing' with a negative comment I totally disagreed with.
Kattunno, I guess from your comment that the only useful thing on the Home page has been removed?
Why would I need to be told there what I've uploaded? Like you, I'm interested in people I have something in common with and not 'everyone'. There's another whole thread about this.