I know that numbers looked impressive but
for example last years English stream had only 8k less viewers during peak (226 638 compared to 218 301)
what is good is the fact that national streams had a lot of viewers which can be seen by overall twitch peak being higher by 80k viewers (321 960 and last year 231 994)
Here stats for this year: https://esc.watch/tournaments/ow/overwatch-world-cup-2017
And here last year: https://esc.watch/tournaments/ow/overwatch-world-cup-2016
here also stats for all the qualifiers to owc (and my threads if anyone interested)
Santa Monica
https://esc.watch/tournaments/ow/overwatch-world-cup-2017-santa-monica-qualifier
(https://www.over.gg/5170/santa-monica-owc-qualifier-viewership-observing#42)
Katowice
https://www.over.gg/5052/katowice-owc-qualifier-viewership#12
https://esc.watch/tournaments/ow/overwatch-world-cup-2017-katowice-qualifier
Shanghai:
https://www.over.gg/4815/number-of-viewers-for-the-overwatch-world-cup-shanghai-qualifiers#3
https://esc.watch/tournaments/ow/overwatch-world-cup-2017-shanghai-qualifier
Sydney:
https://www.over.gg/4893/number-of-viewers-sydney-qualifier#2
https://esc.watch/tournaments/ow/overwatch-world-cup-2017-sydney-qualifier