This looks like a very interesting and potentially clever use for the old Forestry site above Maydena.
There are more details at http://www.maydenabikepark.com, but it looks like they are planning a range of downhill tracks from the Eagles Eyrie site (1100m) down to Maydena, with a shuttle bus to take riders to the top. I've got nothing at all to do with this proposal, and am only an infrequent mountain biker. But I have been to the Eyrie - a few years back - and it seemed criminal that it wasn't being used much. The views from the top are great, the forest below is pleasant, but hardly pristine. It looks like a good way to create jobs in a depressed area.
What would clinch the overall tourism value for me would be if they - or someone else - also opened a rail trail from (say) MONA to beyond Maydena, using the old Derwent Valley Railway line. Then you'd have a broad appeal cycling region, close to Tassie's wilderness, with a need for accommodation, food and lots of other tourism services. It's the kind of development that completely revitalised NZ's Central Otago.
cheers
Peter