if you're attracted to someone's personality are they usually attracted to yours too?

not necessarily. The laws of attraction are complicated indeed.

...It depends on them. Whatever attracted you to their personality won't necessarily be the same thing(s) that attract them to your personality. Everyone has different tastes, likes, dislikes, etc., which means that the possibility of someone being attracted (in return) to your personality is just as great as the possibility of that someone not being attracted to your personality.