I don't expect tumblr to be a twitter alternative. There's nothing like twitter and we won't see anything quite like it again.
I'm back here because I have friends here and I like to see what they have to say, what they're listening to, what they're up to. I like their pretty pictures and silly jokes. It's much more passive here than it is on twitter; I just scroll and like and read in a very pleasant way. I don't interact the way I do on twitter. I just enjoy.
I guess if twitter dies this will fill the gap of knowing how my friends are doing. It won't replace the banter of twitter, the way I feel like I'm socializing when I'm there, but it will be a nice way to keep up, and to share my thoughts and music I'm into.
I've seen a lot of posts from people being mad that twitter refugees are swarming into tumblr and I don't know why you wouldn't welcome more people into the fold, especially people who are coming back after being away for a while. You don't have to follow them! You can just have your curated tumblr dashboard show you only people who are in your immediate circle, but where's the fun in that?
Anyhow, I don't know how much I'll post here but I do enjoy reading my dashboard, and it's good to see old friends popping up. I've missed you. No, this is not twitter. But I don't need it to be.