That's the great comedy here: Everyone succeeding in the chat market has been around for a number of years. Google tries something for about a year, decides it doesn't have enough immediate traction, and then dumps it before anyone even has an account. And they keep abandoning the little shares they gain each time.
If there's anyone who I have to chat with in the Google world, it's likely they still use or have Hangouts, because, including Talk, it's been around for a long time. As soon as Google decided to abandon it's existing, sizeable user base, it basically left the market.