I truly did not expect FW would cook up all these further advantages for their flyers. They were strong enough as it was...
But ya to quickly sum up:
Fighters aren't the king of dogfights anymore as interceptors should beat them regularly. Strike fighters and Air leviathans, which make up slightly less than half of FW's flyers, can choose to skyfire. The air leviathans can skyfire individual weapons if they choose at differing targets, and can choose to skyfire regardless of line of sight, facing, etc in dogfights (assuming they don't die first).
That's all bad news for the razorwing, and to a lesser extent the voidraven. Also... the only FW flyer the dark eldar get is 205 points that you'll literally never field. It's that bad.
I did laugh at the hell blade only getting an agility of 3 though, as I suspect they may have forgotten their own fluff on that one (which mentions it being "supremely agile" twice, while also describing how it can teleport around the battlefield). Then again, when you consider how under-costed it is - I'm sort of surprised it got a 5 pursuit.
Overall, I'm pretty thrilled about the forgeworld update even if it is a bit excessive. I have 2 hell blades and 2 nightwings (converted from high elf dragons) sitting on the shelf that will probably see a lot more of use. I already field a fire raptor occasionally in support of 2 of my armies (mostly just when opponents bring a wraithknight or riptides), but that beast hasn't changed much. Even if no one ever chooses to dogfight - the break turns, bonuses, and further formation bonuses are all welcome.
The dark kin though got hosed as usual. So I hope no one went out and bought a wing full of flyers after DFTS dropped.