The case for Flightwatch services is strong.
* Someone has already raised the problem of congestion. When there's a front approaching, or other weather conditions exist that make everyone interested in conditions at their destination and alternates, there's going to be a lot of traffic on the VHF Centre frequency. The congestion will make it that much harder to get in a call about separation (or even a mayday). A discrete information frequency (Flightwatch) is an obvious help.
* We should not underestimate the intimidation factor. A low-time VFR pilot, or even an inexperienced charter pilot, listening to an area frequency populated by people calling themselves Qantas A, Singapore B, and Falcon C, is going to be reluctant to pipe up and ask for the wind at the podunk aerodrome he's heading for. Anyone who's done their flight training in the past six or eight years has been told that Centre really doesn't want to hear from you unless you're on an IFR plan, and that you're impinging upon the safety of others if you tie up the frequency. Has that changed?
* Local weather knowledge is in decline. Plenty of pilots flying in Australia grew up elsewhere, and so have little intuitive knowledge of Australian weather. Flightwatch provided valuable assistance to these people.
* No equivalent alternative to Flightwatch exists. If we had XM satellite service, or some sort of 3G mobile data service that we could rely upon in the bush, then they'd have a case for taking away the "old" voice service. But there is no equivalent.
Certainly, the service (such as it was) could be better. The Flightwatch operators should have weather radar, for example. But to get rid of Flightwatch and replace it with basically nothing is dangerous. It's going to be a cause of a crash -- quite possibly of a charter aircraft containing six or eight passengers -- before long.