I'm gonna make you a video now and upload it to youtube: it's dark and you won't see anything lol, but you will hear it.
Here ya go: http://www.youtube.com/watch?v=Kf8iJiJSM3I
At the beginning and end of the video the volume is at 11 o'clock, which is regular listening level for me, maybe a bit too loud than it should be, and in the middle of video when its at 1 o'clock it's too loud to listen to for more than a few seconds, and even then its uncomfortable. Amp is Musical Fidelity M1HPAp, headphone leaks almost like an open back.
Yes, looks like they leak a lot.
Well, I'll scuttle off and weep into my T70 then.