I don’t know how much of a true Twitter power user I am, because I never use lists. But these days, I use the service enough that I have come to have one, specific aspect of the service that I loath.
That is, of course, the inability to see only new tweets. I find myself seeing the same old tweets over and over again when what I want to see is new tweets only. I wish there was some feature I could turn on that would do just that.
But as far as I know, that feature doesn’t exist.
I could ramble on about the feature set of a “Twitter Killer” that would fix this and other problems, but since I have no money, can’t code and don’t want to learn, I will refrain.