You need to know the difference between Facebook and Twitter in order to behave correctly in these two totally different environments and so that you can monetize your following as well. 

First let's investigate how Facebook and Twitter differ as it relates to a famous person with lots of followers or friends.  And, let's imagine that the famous person is on stage.

Facebook

Facebook organizes life in such a way that the famous person is on stage and their friends are in the audience.  You may at first wonder: "Where else would they be?" but you will soon see that it is totally different for Twitter.

On stage, everything is planned and prepared.  There are others supporting the famous person so as to make it look like the famous person is doing all the work.  Facebook is like that stage.  The Notes and the Fan Pages and the Groups and the tagged photos and the groupings of photos...  all this is like a huge stage presentation.  The upside is that the stage is impressive; the downside is that it takes a lot of work to create that image and keep it up to date.

Twitter

For Twitter, the famous person is actually NOT on stage.  This is the remarkable distinction between Facebook and Twitter.  In Twitter BOTH the famous person AND the followers are actually backstage, huddled in private conversations.  Actually sharing quiet, fun, casual, interesting moments.  There is no pretentious stage.  There is no necessity, as with Facebook, to be formal.  Of course, you don't have to be formal on Facebook, but that is the culture.

Which Is Better?

At first, followers/friends might like the glossy stage presentation.  At first, the high image, the pedestal, the glamor are all alluring.  But, really, what people want is to know the famous person on an equal basis.  That is not possible with Facebook and it is part of the casual culture with Twitter.

What If One Is Not Famous?

We have just investigated the case of a famous person with a Twitter or Facebook account versus that person's followers/friends.  Now, let's look at ordinary people.  Briefly, no ordinary person has time to establish a glossy showy ever-changing and ever-updated Facebook page.  There's no time in our hectic society.  Twitter requires a name, a photo, a VERY brief bio and that's it.  No need to ever update that. 

Conclusion

For the interaction of famous versus non-famous and for the interaction of non-famous versus non-famous, Twitter is the easy winner.  I predict that Facebook's growth will slow dramatically.  I predict that Twitter's meteoric rise will continue and even accelerate.  Twitter rule