A Samsung spokesperson told Ausdroid this evening:
Samsung Music Hub in Australia has been developed for this country and for Australian customers. It is a separate platform from other music channels offered in other overseas markets.
Samsung Electronics Australia remains committed to Samsung Music Hub in Australia and providing an amazing music experience through our products. We currently have no plans to discontinue Samsung Music Hub in this country.
We don’t have any further advice on the speculation that Milk Music may replace Music Hub here, or augment it somehow, but for those users of Samsung’s Music Hub service, this reprieve is probably good news.