One thing to watch out for here, which can cause confusion when  
reading man pages.

I did an update install of Leopard over Tiger on my MacBook.  It was  
only later (while working over the phone with the boss and finding  
different options listed for a command on the man pages on his Leopard  
machine and on mine) that I found that the man pages on the MacBook  
were those from Tiger.  (The programs themselves were those from  
Leopard.)

All was well on my other machine, where I did a clean install and then  
used Migration Assistant to bring stuff over from a SuperDuper clone.

(I cleaned up the MacBook by doing a clean install and using Migration  
Assistant to copy from the TimeMachine backup [I had two bootable  
clones in reserve].)

   --John