Ooops. Looks like a FAQ/Errata for Tyranids is seriously needed. I don't normally look at big tournament results (been a few years since I did tournaments), but this type of thing shows something seriously wrong. Tyranids dominated all comers it seems at the US Open Seattle Warhammer tournament.
This happens, but for a major tournament it just looks a bad. Congratulations though to the winners though, as I know that just because you have a currently very strong codex it does take work and practice to still pull it off.
What this does do is lessen the experience for everyone else that played, and often that of the winners as well.
Bring on the Errata.
Here are the results.