Have a look at this video , explains it better than I could.
This is body only so you'll have to get one or more lenses.
I'd say this is a potential bargain for someone who wanted but couldn't afford one of these when it came out or who already has a Panasonic body and wants a backup or 2nd body.
A camera system is usually something that either goes mostly unused which is then a complete waste of money or people get right into it and buy a bunch of accessories lenses, flash etc.
I don't think it's a great buy for most people though.