I'm usually slow to voice my thoughts on a new dex before I've played it (Or before it's been officially released). However, I'm always semi-curious on how my thoughts before play testing stacks up to post-play testing...so I wanted to get this out before confirmation bias reforges my memory. Here we go;
Strengths of the codex:
Heavy VC Hive Tyrant w/ Tyrant Guard
Death Spitter Warriors
Here is why I think the above:
Tervigons: Make 3d6 Gaunts each turn (yeah really), synapse range of 18" with Ld. 10. Grants special powers to nearby gaunts/units (Like FNP!), 6 wounds with T6...and he's cheaper than a squad of marines. Expect to see this...a lot.
Alpha Warrior: Better than a SM Captain at a cheaper cost, has access to very cheap upgrades...and can lead any unit. Gaunts with FNP, Furious Charge and this guy leading the bunch. Natural T5 too with multi-wound stat line, so piss off Power Fist. Expect to see this guy leading Gaunts near you.
Hive Guard: The answer to transports for Nids. Str. 8 Weapons that don't need line of sight and decent range....on a T6, multi-wound, cover save getting (yeah infantry class, so gaunts give them cover) chassis. Oh and BS 4. So a unit of 3 puts out 6 Str. 8 shots to pop rhinos.
Zoanthropes: I think (I'll need to do the math on this) that their Str. 10 Lance AP1 shots are better at popping tanks than melta in double dice range. Again, BS 4. Oh and they have a 3++ and can ride in pods. What Land Raider? :)
Ymgarl Genestealers: They have the rules the Lictors should have (No scatter DS, move AND assault the turn they come in. Stealers still beat face and this stealer species has 4+ saves... so this could be a fun unit...but the elite section has a lot of competition. Still a good unit.
Death Spitter Warriors: Good fire-base (A max unit will put out 27 Str. 5 shots!) and they score. They die pretty damn easy losing eternal warrior...but if they are shooting their Warriors with that kind of weaponry the rest of your monsters are safe. Put them in cover, squat and shoot.
Termagaunts: Stealers die too easy now with a 5+ and spike rifles can be decent.
Trygon: Beat stick and deep strikes. You get a turn to shoot it before it starts eating your army (that your Hive Guard just popped out of their metal boxes). He scares my marines.
Mawloc: Pops up like the Trygon then vomits a St. 6 AP2 large blast on you. Oh, he's not much weaker than the Trygon in HTH. And can reburrow to do it again. And has Hit and Run. And is the same cost as a Carnifex. Yeah really.
So there are the units that jump out at me. Honestly, I wanted to do a shooting army like Tau...but damn Nids can be shooty now! Plus, you don't have to ride around in your damn tank all game to only move your troops one shooting phase before they get beat in the head. I'm seriously (I know this will make Mike laugh) considering making a shooty Nid army....if anything just to buck the status quo of HTH Nids and stay away from Transport/Troop 40k.