1: yes it supports HDRI
2: yes it will be ported but i dont know a deadline
3: there is vray free which you can use for free but it has less options than the full version.
1) Oh yeah!
2) Hopefully.
3) There are several versions of VRay: the Basic and Advanced versions are obviously NOT free, but there is also a Demo version that has some features disabled (saving etc.) but it contains ALL FEATURES of the Advanced version. And then there’s a Free version where saving etc. is enabled BUT it doesn’t contain the advanced features. The Demo and VRay Free are -- well, free 8)
For more info, see VRay homepage…