[tbirdtbird]

Play with Facebook all you want.

But be aware that FB uses YOUR computer as part of a peer-to-peer network to promote THEIR content without your knowledge or permission. This opens your computer up to additional virus threats and will slow your computer down. You have to be fairly technically saavy to figure this out, but if you get onto an older, slower computer, and look at the command line ( the very bottom-most left corner of the screen) when FB is loading, you will see a call to a company called akamaihd (in Massachusetts) via this domain:
akamaihd.net
This is the company doing the peer-to-peer networking for FB. Peer-to-peer means trafficking content around across the internet from individual computer to individual computer, instead of paying for a main server somewhere to traffic content all over the place. Limewire would be another example of a peer-to-peer network but they tell you that up front
I personally think this is very sneaky business, and I for one do not want anyone using my computer but me.

If you doubt me, just get on via a family member's older slower computer and you will see it for yourself. A fast computer with a fast connection will load everything so quickly you cannot see this happening (which they are counting on).
One night a yr ago for some reason my connection slowed to a crawl and I spotted this call, and I wondered what the tom hill was going on. Once I figured it out (and confirmed it with a webmaster from another forum I am on), I dropped FB forever.

Let the user beware.