Okami's Amaterasu certainly isn't the only third-party courier to make a cameo in Dota 2.
This isn't the first time that DOTA has been used as a means of promoting video games, or indeed TV shows. There's even a short clip that shows Amaterasu in standard and flying courier animations.
With Okami HD, an incredible remaster of a beloved PlayStation 2 classic, coming to PlayStation 4, Xbox One, and PC - it's no surprise that Amaterasu is back in the spotlight. So far though, it looks as if Amaterasu's inclusion would be inevitable given the very positive response from participants of the poll campaign. She battles demons, defends ancient Japan and is a Sun Goddess. If you're more of a League of Legends person, you can still enjoy Amaterasu's prettiness by playing Okami HD next week.
Okami is a gorgeous game and the art style hasn't been lost in the transition to Dota.
This sudden move to have an Okami courier in Dota 2 might actually be a tie-in with the upcoming Okami HD remake coming out later this month. Now she can bring you your slippers (of agility) in Dota 2. When a player normally purchases an item, it is stored for them at their fountain (the respawn location of each team's essential home base).