The brand new profile pages are a customisable page to show your cards and boards. With a custom username, header image, and profile colours, you can really make your profile yours.
There are 3 tabs on your profile page:
The pinned cards tab allows you to select any number of cards from your (public) boards to appear on your profile.
The cards tab will display all of your created cards, only showing cards from public boards to any user other than yourself.
The boards tab is similar to the cards tab, it will show all of your boards with only your public boards being visible for other uses.
Check out our profile here.