Microsoft bribing you to use Bing?

I, like every other person on the planet, use Google and not Bing to search the web. However, I was trying out Cortana on my newly-installed Windows 10 (review coming soon) and it used Bing automatically. It was by doing this that I discovered Microsoft have actually invented a way of bribing you to use their search engine! Has anyone else seen this?

Let me introduce you to 'Bing rewards'. 'Search Bing. Earn free rewards.', Microsoft says. This includes gift cards from Amazon, apparently. So they are literally giving you money for using their search engine... interesting marketing strategy.