I don't think Hacker News has any interest in comparing itself to other news sites, but direct comparisons have been used successfully in advertising before. I don't think it's annoying in this case because nerds are typically just not drawn to the whole sports scene (at least the ones I know). I see this more as a message to nerds saying "hey we are running this type of sports broadcasting that doesnt suck because it's not boring. By the way, it's going to be huge--tons of people are already watching."
It's not really a direct comparison though, this is more of a category comparison of esports vs traditional sports. It's not like JustinTV is saying "our site is better than MLG and GOMtv combined!" I see them as promoting esports in general, which is actually very good for the gaming scene overall.