I don't know--the graph in downloads shows that I'm getting the 100KB bursts every 60 seconds. This is almost identical to what I saw when my ISP experimented with NBAR and Sandvine p2p controls.
I tried another magnet from
http://www.magnetmix.com/index.shtml and that came through fine. Looks like your server/ISP is involved. Let me know if you want the screenshots, or better yet, install a jum or LW and check out the upload graphs yourself.
Has Dave added any way to add an advanced stats module to Acq?