I've got my HTC 8S a while ago, since January this year. I haven't gotten any notable problems with this device, but last night while I was browsing I saw a lot of green and red dots on my screen. So I searched on the internet and I found out that my 8S has a lot of dead subpixels. I immediatly contacted HTC, but they say there must have been "some external pressure" on the screen and that caused the dead subpixels, they won't pay for it. I carried my 8S like it was my baby! It has only been in my pocket, on my desk and in my hands, I even didn't allow anyone to borrow it! I'm very mad at them and will never buy an HTC device again.
If the pixels are black, they are dead pixels. If the pixels are any other color, they are simply stuck pixels, There are a couple of videos on YouTube that can fix stuck pixels, along with the eraser trick of tapping on the screen with a pencil eraser.
I had the same problem. Send it to HTC and got a brand-new device back. You should send it to HTC Netherlands :p
You should contact them again, and say it are around 50 (I Guess, same with me) dead pixels. 1 or 2 they don't mind, but more than a given percentage of the screen is according to the law (maby not in your country) a good reason for replacement.
I wish you good luck, and contact them again, a couple of times. It could help.