FYI: I sent a follow up email to Pioneer about my situation - basically it went along the lines of...
I've watched only other shows, dvd's, xbox and other material for the past three weeks and had the screen running with just random static noise (untuned station) for a few hours to try and remove it but whilst it is mostly faded now (and basically not visible during normal viewing unless there is a flat area of colour over the relevant area near the top right of screen) it is still visible if I switch to say an all white screen.
I've checked the hours on the panel now and it is up to 120 hours.
It has seemed to have faded quite a bit since that first day but it is definitely not totally gone so I'm not sure how long I should wait? Obviously Channel 9 have recently changed their logo but I'm still reluctant to watch long term sports (cricket on 9 or tennis on 7) because those channels still have a bright white static logo. This seems a little unreasonable however since quite a bit of the point of getting this large display is to watch these sorts of shows?
As an active forum member (e.g. DBA, XBZ, etc) I've noticed quite a few people with same or similar panels experiencing no problems at all with hours or days of static viewing whereas others like myself have problems with very limited viewing - perhaps it is an inconsistency in production?
and their response:
Quote
Thanks for the update, it usually takes up to a month for these images to disappear totally.
It is preferred in the case mentioned that a moving picture for example channel 7 and 9 etc is to be played because this forces the cell to display different percentages of colour not a random burst of pure white/black. The more colours displayed will move the perception of vision alot quicker. I would recommend to watch movies or standard free to air as this black/white static channel wont do the same job as a proper programmed channels.
This was about a week ago. Since then I've noticed that mine has almost faded to nothing now - even with flat areas of colour now it is very hard to see - sometimes you can't. I tried to take a photograph of the mark with an all white screen but whilst I could "just" see it with the naked eye it doesn't appear in the photo at all. Here's hoping it goes for good