Maybe a bug:
1. Do a multi-file search and replace, 2. bring the main window to the front (text windows with tabs), 3. save all windows (command-option-s), 4. and close the window.
You'll see the find window and its results below. 5. close this window 6. click "Save All" when you get the "Do you want to save the changes from your replace operation?" prompt. 7. Forever beach ball! Force-quit required.
Oh, wait—I just tried these steps again without trouble. So, maybe never mind? I'll let you know if it happens again.
Quinn