Plasma TV's are bad if you don't plan out your placement and wiring needs. If you have an entertainment center that includes a plasma mounting option (usually a false wall) then you are probably planning on wall mounting it. If so then you need to be very aware of how you are going to get power to the TV, and ultimately how are you going to conceall all of the wires that will need to run to the tv from your various picture sources...cable/satellite/dvd etc. THis can get expensive in a hurry...I just did a plasma setup for my sister in law and the wire connectors (parts alone) were close to $400. That doesn't include the wires you'll need to go from each of the components to the wiring panels which will add another couple hundred to the total.
So I guess to answer your question Plasma TV's are not bad - poor planning of a plasma tv purchase and installation is bad.