here's a test. connect to my computer over a skinny DSL line,
AFP://pseudohacker.com - (my upload cap is about 10KB/s)
connect as guest, mount the public directory, then do a file listing and while your computer is grabbing all of the silly information for listing files see if it does anything other than piss you off. If it can, then the Finder is multithreaded and the I/O model is greatly improved.
Sounds like it is multithreaded, and it damned well ought to be. The "other Finder" has been languishing in miserable crusty abandonment for many months now. If they haven't been working on a good multithreaded Finder then I think I should be allowed to punch every programmer involved in the arm. In their good coding arm. And Steve-O gets a kick in the shins for not making it happen. Not that I'm bitter about the performance of the Finder and the I/O system or anything. Anyone else get predictable kernel panics on massive copies of small files over AppleFileSharing? grrrrrrrrrr.