Moah nooz from da roomah mill:
Tyranid Weapons are no longer dependent on the statline of the carrier, they all have set statlines. Argh.
Each weapon is divided into light and heavy versions (don't worry, they're still all Assault weapons) for use by smaller or larger Tyranids. Gone are the Strength 8 Barbed Stranglers and Strength 10 Venom Cannons (although Venom Cannons do get a small blast...). Ah well, my Barbed Strangler Carnifexi are still just as effective against most of my opponents and they actually gained a point of Armor Piercing!
There are a host of new weapons such as the Sting Blaster, Spike Blaster and Texorin Bug (which functions much like a Blastmaster with multiple fire modes, all template ranged). All of these weapons seem like they focus on short-medium range, high strength (mostly 5s and 6s) and low AP.
The new Biomorphs are much different than the older ones. Each one gives a Special Rule of some sort to the bearer rather than an increase in stats.
For example, Toxin Sacs now give 4+ Poisoned Attacks, Adrenal Glands grant Furious Charge, and Wings make the unit Jump Infantry.