switch(config)#tacacs-server host 192.168.9.25 This cli will be deprecated soon. Use new server cli
It seems that part of the reason for the change is so that you can now specify an IPv4 and IPv6 address for each TACACS+ server.
Listed below is the old school TACACS+ configuration I was using.
tacacs-server host 192.168.9.25 tacacs-server key rycserdOb ! aaa group server tacacs+ TAC_PLUS server 192.168.9.25
This now becomes:
tacacs server AUTH address ipv4 192.168.9.25 key rycserdOb ! aaa group server tacacs+ TAC_PLUS server name AUTH