Macros in an action:
HOST.NAME: {{HOST.NAME}:test.item.last(0)}
HOST.HOST: {{HOST.HOST}:test.item.last(0)}

in an alert will be expanded to:
HOST.NAME:

{it0:test.item.last(0)}

HOST.HOST: 21

Note that with the

{HOST.HOST} it works correctly, but with the {HOST.NAME} - it doesn't expanded fully.

Of course the macro {HOST.NAME} is new for version 2.0 but it must work identically to the {HOST.HOST}

(a replacement for

{HOSTNAME}

)

http://www.zabbix.com/documentation/2.0/manual/appendix/macros/supported_by_location