Why Facebook instead of email?

In class, someone asked, "Why use Facebook instead of just emailing someone?"

Honestly, for just sending a single message to a single person, there's no reason to use Facebook. Facebook is a social networking tool, used for connecting with a multitude of people. Here are some ways that Facebook is better than email:

share photos and videos

search for old friends, classmates, etc.

invite people to an event or meeting

play games online -- with a friend, a stranger, or a whole group of people

get reminders of your friends' birthdays

create a small group (sub-set) of your network of people, such as a club or class

ask your entire network for advice or suggestions, such as a recipe, book or travel destination

all your contacts' email addresses are catalogued in Facebook; no need to keep an address book on your computer

access friends' emails and information, from any computer, even when you travel

This article tells of five charitable campaigns that were successful using social media tools.

What do you do in Facebook?