General progression of communities now is multi-platform. Roll with it, Facebook might respond to certain things that a forum doesn't - but, forums can be pretty powerful at creating your brand ambassadors and also for search engine traffic.
Looks nice. I like that it is responsive as well.
The key will be keeping a very functional user interface - the types that browse forums now care about that.
Design wise I'd go easy on the radii and gradients (those were last decade trends). I'd probably also mute some of the color and play with the typeface.
Tell the developer to really take care with page size - because for mobile this is essential, especially when your doing it responsively. Optimize everything. You may want to look into using a CDN. Careful with the javascript - stuff gets fat fast and mobile devices hate that.