It's nice to hear of other people with a similar stack on HN (Azure, PowerShell, TeamCity, HipChat, and presumably C#/.NET)! It's working well for us too.
In addition, we're increasingly doing more with ChatOps with mmbot (as an Azure Web Job): https://github.com/mmbot/mmbot
One nice thing about mmbot is that if you use the DLL mode instead of the CSX mode, you get a great IDE debugging experience which makes it even faster to create meaningful ChatOps extensions. I've found it to be a more pleasant development experience that Hubot with CoffeeScript.
Hah, we also use mmBot, but while it was our original plan to have it be our "DevOps 1 stop shop" we ended up shying away from that idea in favor of a more hands off approach. We still use our mmBot for a lot of back-office querying type operations, but decided that, at least for the moment, TC/Octopus will be our way forward.
In addition, we're increasingly doing more with ChatOps with mmbot (as an Azure Web Job): https://github.com/mmbot/mmbot
One nice thing about mmbot is that if you use the DLL mode instead of the CSX mode, you get a great IDE debugging experience which makes it even faster to create meaningful ChatOps extensions. I've found it to be a more pleasant development experience that Hubot with CoffeeScript.