We've made some updates to this in version 1.6 that will improve the content caching for most circumstances. In addition to it just working in a single VM, we've also provide JMS listeners that can be configured to flush the cache Take a look at JMSArchivedPagePublisher and JMSArchivedPageSubscriber components. If you wire these up with a valid JMS implementation, then content pushes will be near-real time in a production environment.
Without wiring these up, the content cache time is controlled by the following ehcache configurations that you can override in your cache configuration for quicker timeouts.
<!-- Page Cache - 1 hour cache -->
<!-- Structured Content Cache - 1 hour cache -->