[dnanian]

And, indeed, it shouldn't.

If it gets stuck again like this, please open Terminal. Then, copy the following to the clipboard:

sudo lsof | grep SDCopy

Paste that into Terminal. Press Return at the end of the line, then enter your password (it won't echo) and press Return.

That'll print a list of what we're copying at the time -- the last two lines are what we're reading and writing. Hopefully it'll give a clue about what's happening... very strange.