Even though we already had information that this is coming, there is now a leaked image of the upcoming release for Tyranids, Invasion. So check out the leak, and get ready, Tyranids are getting more formations to add to their arsenal.
Here is a link to the site with the pics. There are more White Dwarf leaks on the site as well for this weekends Dwarven releases and pre-orders.
http://astropate.blogspot.com/
Here is the article from yesterday talking about the release.
http://natfka.blogspot.com/2014/02/tyranid-invasion-dataslate-incoming.html