They released hours of videos, dozens of tweets, articles, AMAs on Reddit, invited streamers to play in the beta for the card game, …
Like @Menzo said and was mentioned in the League thread, it’s the 10 year anniversary of the game’s release and they have pulled out all the stops news wise. They are celebrating Riot, the League community and finally putting a real s into Riot Games.
You can check out their Twitter account for a taste of the current activity: