Is PostgreSQL 9.2 autovacuum sufficient for a busy table?

Question

I have one table on a PostgreSQL 9.2/PostGIS 2.0.1 database:

CREATE TABLE ch02.markers  
(
  ff_id SERIAL PRIMARY KEY,
  col1 boolean,
  col2 smallint,
  created_at timestamp,
  lat double precision,
  lon double precision,
  geog geography(POINT,4326)
);

CREATE INDEX idx_markers_geog ON ch02.markers USING gist(geog);

This table is having records, probably thousands but potentially tens of thousands per hour, inserted and deleted 24/7.

I am wondering if the default autovacuum settings will sufficiently manage the table?

Otherwise I presume I write a SP function that is called by cron. However, what should I use? VACUUM ANALYZE? I am wary of using any anything that locks the table (CLUSTER, REINDEX). Do these even work for an index on a geography point column?

I am not used to such active tables and I am completely new to Postgres, so I have absolutely no feel for this. Any help appreciated.