As many people have already said, Games Workshop have updated most of the 40K FAQs today, and most importantly added one for the Necrons! In general, the only nerf I can really see is of Scarab Spawning tactics, no more conga lines across the field, however probably the best thing is the confirmation of members from different Royal Courts being allowed to join the same unit. The Gauss Flayer Array has been cleared up and now acts like the old Monolith Flux Arc for purposes of line of sight - if one of the Flayers is in and LoS and range then the entire array counts as being in LoS ("As long as you can draw line of sight along one of them, you can target the unit") which is rather brilliant IMO - hiding a Ghost Arc/Doomsday Arc mostly behind a piece of terrain but with just the front Flayer in front of it could be useful; you'd be able to shoot with the Array but would count as in cover/out of LoS for purposes of them shooting back at you from the side.
They also cleared up a issue that I had before with how Entropic Strike is distributed in vehicle squadrons "Split the successes equally between all member of the squadron with any excess allocated by the squadrons controlling player. Then roll to penetrate as normal.", and I do like that they have confirmed that you roll for Entropic Strike and to penetrate, as well as the fact that if there are multiple units in the CC, then the other ones only roll to penetrate after Entropic Strike has been resolved if at the same initiative. Only other thing that I previously had a question about had been concerning Trazyn the Infinate's "Surrogate Host" ability, but that too has been cleared up - he rolls for Reanimation Protocols first and then if he fails that, he makes his Surrogate Host roll.
All in all I think it was a pretty good FAQ update, we haven't been completely nerfed which is nice for a xenos army, and I can't say I'm surprised at the removal of Scarab chaining across the field. I do honestly think that the new Necrons might be one of the most balanced armies in 40K at the moment - we have some pretty powerful things but do pay the points cost for it and don't appear to have anything game breaking at all, or anything that will make everyone drop any other army just to pick Necrons up. The only thing I'm sad about is the lack of a Flayer Lord - even if it meant your army was significantly reduced in what options it could take, (like no vehicles, nothing from the Triarch and no Lords that weren't Flayer Lords) it would have been a nice fluffy additions, regardless of the actual strength of the army, as well as the lack of say Destroyer Lords moving Destroyers into the troop section, or a SC that made Lychguard/Triarch Pretorians troops. However, I can't complain, compared to the old one, I'm loving having so many options and so many brilliant models - just hope we get the DE treatment instead of the Tyranid one!