Maybe if it were Apple these would be the only two options. Unfortunately Google does a lot of "half ass" launches. By that I mean they release a product that is the "Google version" of something else that is out there. But they do no marketing, so unless it's amazing like Gmail or Chrome the most likely option is what happens to most things Google clones:
c) Google launches, and some people use it... but not enough to make a dent in Groupon, but just enough people to justify running the service
I saw a big billboard ad for the Chrome browser on a UK motorway a couple of months ago. I was very surprised, at least until I saw an IE9 billboard in a petrol ('gas') station the other day.
c) Google launches, and some people use it... but not enough to make a dent in Groupon, but just enough people to justify running the service