All I can say is to be persistant with Samsung... very persistant.
We fought with Samsung over our TV for a couple years with them continually denying any issue with the model we purchased. However, if you looked around on the internet, there were all sorts of dissatisfied customers who were dealing with the same issue. Basically, what happened was this - the primary circuit board had incorrect capacitors on it. These capacitors were popping, which caused the initial power-cycling problem. Problem was that since the issue wasn't "known" by Samsung, when you turned on your TV once the capacitors had blown, it would cause the circuit board to fry.
Finally, after fighting with them for over a couple years, we suddenly got someone on the line who was a bit more resposive. We were told that before anything could be done, they would need to send someone out to exchange the circuit board. I told her that the circuit board was no longer available for purchase (and included my findings as to the defective nature of the boards), but was told that someone would come out to look at the set... and I recieved a confirmation e-mail for the repair time.
The day before the "repair" was supposed to take place, I suddenly got a cancellation e-mail... no reasons given, no options as what to do next. Needless to say, I called Samsung back to find out why this was cancelled. Their answer - "Oh, that circuit board is no longer available." (in other words, what I had told them before the repair was scheduled). I was transferred to a manager.
The manager asked what I was looking for... my response was simply to have a working TV. To my surprise, he actually started talking about options as to what they could do for me. They started out with lowball offers -- DO NOT ACCEPT SAMSUNG'S FIRST OFFER, but eventually I was able to convince them to send out a set that was much better than what I originally had purchased (I mentioned original cost, plus repairs, and time and effort contacting them). They shipped out the new set, and disposed of the big old DLP paperweight for us.
So, in a nutshell, Samsung did make good... but persistance is the key!