[UPDATE] Telstra's Facebook page has been updated with:

All - Telstra lost connectivity with the international data network around 1:40pm this afternoon, which resulted in an overload on domestic sites, causing issues with internet access.

 

The vast majority of customers are back online, but our engineers continue to monitor the network.

 

Call volumes are high to our customer service channels because of this outage and we appreciate your patience.

 

We'll keep you updated as soon as we can.

BREAKING: Telstra are experiencing a massive outage to their services, which seems to be affecting not just normal ADSL customers, but Cable-based, Next-G, Satellite and more. The outage started about an hour ago and has been quickly spreading.

Telstra's own Facebook page has been updated with the following message:

A service outage has been identified which is resulting in intermittent internet access. This is being treated as a matter of high priority. Thanks for your patience.

We're seeing discussions all over the place right now, with a news story on IT Wire, discussions on Overclockers Australia, AusGamers, and more.

Telstra's Service Status page says everything is OK, but was last updated at 9am.

This post will be updated as more information is released.