Whether burn-in is still an issue depends very heavily on how you use the OLED TV. I have my OLED TV for almost three years and no burn-in. I know there are tests that show that you can provoke burn-in, but that is with rather extreme scenarios. If you don't have static elements on for hours at a time, you generally shouldn't have an issue. One thing I've heard, but that doesn't apply to my usage is that e.g. putting on TV stations with static chyrons in bold colors can lead to burn-in.