I attended the European SharePoint Conference in Stockholm. The most important information about the first day were the two keynote sessions. You can read all about it in the article from Benjamin Niaulin: SharePoint is back, stronger than ever.
At the end of the day there was a hackathon organized by Jeremy Thake from the Office team at Microsoft. We were able to create an Office Add-In from scratch with some help from guys from the product team in Redmond. This was a cool experience and I had to chance to meet some interesting guys. I teamed up with Nick Harvey from London, UK and created an add-in for outlook.
Check out the Hackathon Teams Submissions. http://espc15.devpost.com/submissions