Microsoft distinguished engineer Blaise Agüera y Arcas is joining Google. Agüera y Arcas originally joined Microsoft in 2006 after the software giant acquired his Seadragon startup. He was a key software architect that helped develop and build Microsoft’s Bing Maps service and its image-stitching Photosynth software. The New York Times reports that Agüera y Arcas will work on machine learning at Google, something Microsoft’s research teams have been focusing on heavily recently. Agüera y Arcas describes the decision to leave Microsoft as the hardest decision of my life in a blog post confirming his departure.