I've only just discovered dailymile and really like the idea of tweeting when I do some things. Two problems -

A lot of my friends are on Nike+ so I like running tweets coming from there and having dailymile duplicate would not be ideal.

I don't want some other things tweeted - While giving running stats might be good and help encourage and motivate me, friends might be less interested in my weight-lifting that I do daily.

Therefore I'd quite like more control over what specific types of activity get tweeted.