It looks as if some of the new Tyranid playtest material may have gotten leaked over on 4chan recently as a ton of very specific rumors popped up overnight
So who know whats going on for sure, but Tyranids appear to be next on the release list for 40k (along with Imperial Guard, Orks, heh and more, lol)
Here’s the latest courtesy of Faeit -MBG
There is a large group of Tyranid rules that are now floating around on 4Chan and all the forums by now. Its hard to tell how good of a rumor this is, so take it with a little extra salt until we can get more information. In my opinion, if this is real in any way, its from playtest material.
Please remember that these are rumors, please add some extra salt on this one
http://natfka.blogspot.com/2013/08/tyranid-rumors-erinye-harpy-plastic.html#more