It looks like GW got their act together and posted a quite elaborate list of new FAQs.
- Tyranids Shadow in the Warp now effects Psykers in transports
- Hive Guard now ignore cover saves in nearly all regards. The only cover saves you get are from area terrain. Many are claiming this will also ignore smoke launchers, custom force fields, and flat out skimmers/turbo boosting.
- Jaws of the World Wolf doesn't require a To Hit roll as many were claiming (good for them, bad for Tyranids LOL)
- I was right about the Doom Scythe. I already took the time to point it out to each individual that said otherwise on that youtube channel.
- Lychguard are unable to use their shields against anything that isn't AP3 or lower (which means no reflecting)
- Lash needs a To Hit roll now.
- No flicker fields against difficult terrain rolls.
- A big nerf to IG and Space marines (mostly) for casting powers out of a transport.
A few other minor changes as well.