[mheap]

We don't filter anything out, as that's against Twitter's ToS. We do however facilitate sending all tweets from a user into a folder you define. You can of course decide not to read that folder :)

The UX on creating filters needs work, I agree. You can make filters as complicated as you like! e.g. "Any links tweeted by @tweetdigapp with the hashtag #opensource".

We have metric tracking for most user actions. Home rolled though, and I've not heard of Mixtab. Will take a look at them, thanks.