I too am experiencing screen bulge and yellowing of the screen on the top and sides. I contacted Microsoft Helpdesk and they said that since it is out of warranty I need to shell out AUD 850 for a replacement of the same model computer.
This response from Microsoft is rather disappointing given that this is a manufacturing defect and they cannot wash their hands off the product just because it is more than 1 year old. After having spent a considerable amount of money purchasing this product, I did not expect that it will just last less than 2 years!
I hope continuing to use the existing product does not create a safety issue in the long run. Microsoft should really recall the products in the field before this becomes a major fiasco for them due to safety issues and loss of brand image due to release or inferior products into the market.