It kind of looks as if they got weaker over the last two days of usage. Could be my wishful thinking, though. With white background, the spots (still) are noticeable and distracting. It's like with dead pixels: once you've discovered them, you can't ignore them anymore...
That's too bad. I see some guy recently bought One X find this problem and immediately went to shop for replacement a new one.
BTW, do you test it by run some HD game for a while which can cause the phone very warm, and maybe yellow spots will be obvious? Quite many Sony LT 26i phones has yellow spot discovered after it go for 40 C temperate. And when it happen later it never gone. Sony admit it is the problem.