There has been a lot of hate on the Internet about the new book. But some crucial points have either been missed or brushed under the carpet.
A lot of units have a sizable points reduction. Anywhere between 20 and 25% in some cases. Their statistics mostly remain the same.
They now also gain a bonus attack from two sets of melee weapons. Something they never used to have.
For me, most of the book is usable with a couple of exceptions. The Tyranid Prime is massively over priced now, and I think everyone could see Tervigons being hit by the nerf bat. Lictors, previously the worst unit are slightly improved now having infiltrate. The Deathleaper is a really good unit.
Boneswords being AP 3 didn't surprise me. It doesn't affect MCs but warriors suffer. But were you really expecting them to go up against terminators? I didn't think so.
Daemons got similar points drops and they had reductions in statistics. Their book is very usable and I really see no reason to not think the Tyranid one will be too.
Also, the Tyrant gets very cheap wings. Expect to see ALL flying tyrants unless someone stumps up the points for Swarmlord and Tyrant guard.