How is Asana? I've been following it for about a year and it looks like a really solid project. I was impressed by it and think it'll do really well, but I haven't had the chance to actually use it.
It took me about a day (since I did not have time to watch the video tutorials) to set in mind the new terminology. But day after I have moved in all open tasks/issues, invite teams in and it feels as I have come to the promised land of GTDc (Getting Things Done Collaboratively).
I've been using it for a few weeks now and really like it. There are a few clunky bits and I've yet to find a way to send them feedback. That said, it's a product I wouldn't mind paying for.
I just hope they release a mobile app sometime soon after launch.
However, I last week I got asana invite, and currently using it to keep up with 4 on going projects.
I guess I would not use this one at the moment.