It's a shame it took me this long to find this thread as well. I've been through a lot of what everyone has described unfortunately and I'm a little too tired to go through it all but I'll try to sum up.
Bought my set at best buy, 5071 in Feb 2007 (I think). I hit the blinking 12 lights pretty early on and called best buy which referred me to pioneer. They had me talk to their local service guys and here's what we went through:
1. Came out and replaced my main card, that didn't work. Took my tv away for about a week
2. Turns out the replacement board they sent me was bad along with the sound board. Had all that replaced.
3. Blinking light comes back on. Had the guys come out and replace the main board again.
4. No luck, I think they did the upgrade with each new board. Tried the 00000 for the tv guide but no luck.
So I called pioneer to complain but they pretty much brushed me off. They told me they didn't have a solution and couldn't do much for me. This was probably back in September of 2007. Pioneer wouldn't do anything to help me out, I asked for replacements, trade ins, etc. No freaking luck. I'm really disappointed with their lack of concern about customer satisfaction. I know we all agree that when you spend top dollar you expect top performance. The TV looks nice when it works but when it randomly turns off it's pretty annoying especially when playing games. Now my new PS3 is doing this blinking issue that I've heard about and it sounds like it's related to a handshake issue (although I'm not using HDMI so I don't know if this applies). In my research that's how I found out about this thread.
So I'd love to hear if some type of lawsuit comes about similar to what happened with the Xbox 360. I'm stuck between a rock and a hard place b/c my warranty is out. Should've saved my money and bought a Panasonic or something. How lame. Maybe I'll give pioneer a call and tell them that none of their help worked and that I still deal with the blinking blue lights.
Now that I think about it, one of their techs explained it as the TV is trying to get updates OTA and doesn't get a full signal and bombs out. It sounds like people with OTA and cable are experiencing this problem so it sounds like a stall answer to me.
I'm extremely disappointed, I hope that Pioneer's Elite series isn't this bad. I'd like to go out and get one just to get rid of this issue but it'd be ridiculous if I spent over 6,000 dollars and ended up with an distempered TV. Keep me posted on your experiences and I'll try to update the forum with my luck. How's that for a first post!