BUG #9457: replace materialized view?

The following bug has been logged on the website:

Bug reference:      9457
Logged by:          Dylan Simon
Email address:      dylan-pgsql@dylex.net
PostgreSQL version: 9.3.3
Operating system:   Linux
Description:        

It would be nice if there were a way to change the query definition of a
matview, presumably with "CREATE OR REPLACE MATERIALIZED VIEW".  Obviously
the same restrictions on replacing a view could hold.  I haven't seen any
mention of this as a planned feature or anything that would prevent it.