I typically have only one buffer window open, and my programmed muscle  
memory includes the sequence ^X-2-^X-^B.

This used to result in the cursor ending up in one window, and the buffer  
list in the other window.

After upgrading to 24.4, it seems that the cursor now winds up in the buffer  
list's window.

It looks like that with one window open, ^X-^B ends up doing what ^X-2-^X-^B  
used to do. Instead of retraining my fingers, I'm hoping that it's possible  
to flip some knob, and restore the previous behavior, but list-buffers' help  
is silent on this subject matter.