As people seem to be starting to play games and get a good look at the new book i've opened up the Tyranid tactica Discussion. This will act as a summary post/point to other posts where appropriate.
Nidzilla still looks to be viable in a different form, especially with cheap units of warriors as troops and probably trygons instead of fexes.
This might utilise lots of mid size creatures such as Hive Guard, venomthrope, pyrovore.
Warriors with two boneswords and possibly wings with the biomorph giving 4+ poisoned attacks appears to be an effective anti MC/HQ.
Brood of Zoanthropes in a spore capsule appears to be an effective Anti Heavy tank choice.
Hive guard (don't require LoS) would appear to be effective as they can be hidden in a building/ruin/in or behind area terrain. Shooting wise they are like a marine with 2 krak missilies with a slightly lowered AP. They can take out transports such as Chimeras and Rhinos from a long range with relative ease. They are also cheap, see WD Jan for points cost.
Large broods of Hormagaunts or Gargoyles are cheap and are good for quickly tieing up enemy units allowing your MCs to get into CC.
Venomthropes are good for providing large broods cover saves and some protection from pizza plates. Because only one model needs to be in range a large unit of 30 hormis can leave a small conga line behind to stay in range. Defensive grenades are also useful.
The unit spawn list also looks to be possible. This comprises of Tervigons that spawn Termagants, Biovores and Harpies to spawn spore mines, and the special character that allows you to potentially turn outflanking units into rippers. However all of these are situational and the ones that give you lots tend to run dry...
Flyrants hidden in unit of gargoyles allowing cover save with paroxysmto help keep safe from nearby enemy units.
Stealers with broodlords act as new vanguard army. Alpha warrior as HQ may fill the role of Broodlord as an HQ.
Shadow in the warp will help stop MCs succumbing to Force Weapons now EW has been removed.
Cosmic Girl's excellent unit summary can be found here: http://www.warseer.com/forums/showpo...0&postcount=71
And for special characters:http://www.warseer.com/forums/showpo...&postcount=143
itcamefromthedeep's biovore mini tactica can be found here:http://www.warseer.com/forums/showpo...&postcount=110