I rated 43 films, then selected "Top Picks for You" and got 0 results. So I decided to not watch a movie and instead go for a walk. Which turned out to be exactly what I needed. Five stars.
It seems that recommendations by the "wizard" mode are updated daily or so. I signed up yesterday and got nothing with the wizard mode. It starts to show promising results just now I checked.
Edit: It seems that the "wizard" mode is updated daily or so.