Does issuing DDL against a view in PostgreSQL take out the same locks as issuing DDL against a table?
Direct answers to your three questions would be;


Yes it does. When you replace your view, the lock of view object will be AccessExclusiveLock.
Yes, even the 'select' queries that uses that specific view will wait until the 'create or replace' statement is committed.
Yes they do. After the "view changer" query is committed the queries that are waiting will start