Adding Custom User Profile data based upon Categories

Question

Based upon the code found here: How To Add Custom Form Fields To The User Profile Page?

How Could I alter this so that users could check one of several boxes based upon categories I have setup in the blog.

E.g. If I have categories:

Apples Oranges Bananas

Id like these to appear in the User Profile area with a checkbox next to each so that a user can select which fruit they like best.