After upgrading to Leopard I switched to Miro from Transmission, which seemed to cause several runaway Spotlight MD processes, possibly because Spotlight in 10.5.5 has trouble with incompletely downloaded Transmission torrent files. I stopped using Transmission and haven't had any trouble since.

But the Miro learning curve is long and challenging. I'm on my 2nd week with Miro and still can't get it to automatically download files. On my system, the "Auto Download: New" drop-down menu doesn't seem to function, and unless one manually searches under the "Items in this Channel" Ajax drop-down section, one won't see all the new available downloads.

The concept behind Miro of a single media player for all file types is quite admirable. But this is in no way an "at-a-glance" interface, and it seems incredibly counterintuitive and frustrating.