Of course we will provide Max 2013 support for all our plugins. We have much work already done with the new release, but it will be needed some time to get a final version, because Max 2013 adds drastic changes that require testing.
Approximately, this will be our roadmap:
1) First we must wait that ChaosGroup release VRay for Max 2013 (a final version, not beta). We need it to compile and test our plugins.
2) We will release beta versions of Forest Pro and RailClone Pro (available for all registered users of Pro versions).
3) Once the Pro versions are fully tested, will will publish stable versions (Lite and Pro) of the plugins. I think the beta testing phase should not take more than 1 or 2 months.
Probably our other free plugins (Glue, Clone, ColorEdge) will be ready in a few days after the Max 2013 release.