I've been using Windows 10 for a while now at work and I haven't seen any ads yet. I was really enjoying the different pictures on the lock screen and the way you can like/dislike them to get more of the types of pictures you like. If they start running ads on it and I have to disable it that's going to be pretty sad. I mean, not really in the grand scheme of things, but it was a pleasant, enjoyable feature that made me like Windows. Why ruin it with ads?