CREATE TABLE LIKE, regarding constraints

www.postgresql.org/docs/9.0/static/sql-createtable.html
== == == == ==
LIKE parent_table [ like_option ... ]
. . .
Not-null constraints are always copied to the new table.
CHECK constraints will only be copied if INCLUDING CONSTRAINTS is specified; other types of constraints will never be copied.
. . .
== == == == ==

But I do see PK and UNIQUE constraints
CONSTRAINT blah_pkey PRIMARY KEY (id),
CONSTRAINT blah_host_id_key UNIQUE (host_id)
in the def of the new table.

Also, why is there no discussion of what "EXCLUDING CONSTRAINTS" will result in ?

Thanks,
-dvs-