Edit: here's a thought.
Thanks again for your support of Product since our launch. It means the world to us, and it's been a terrific ride for us. Unfortunately, we haven't seen the broad usage of our service necessary to sustain it and we'll be shutting it down in X months. Luckily, BigCo is acquiring our team, which means that we'll have jobs making their quasi-similar product even better.
Here's how you get your data: (blah)
Here are some similar services you may want to consider moving to: (blah)