I use my OLED TV as a monitor almost exclusively, for the better part of a year now too.
It has some issues with IR (in cases of extreme colour saturation over contrasting backgrounds) but these resolve themselves in seconds. Absolutely zero problems with burn-in. TN/IPS/VA panels all can exhibit burn-in too, if you leave a static image there for a long time (a lot shorter than you think too).
Burn-in is not something to be fearful of, unless you have no clue how to prevent it. I've owned plasmas too and have avoided it every time. This bug-bear/FUD was cooked up in the early days of these technologies, usually gleaned from white papers which referenced versions of these technologies that never made it on to store shelves.
My LG set uses pixel orbiting that prevents this issue, while the recently released Dell OLED has a high frequency, strobing refresh which also combats the issue (and has the added side-effect of improving motion resolution massively). OLED monitors will be the enthusiast standard in due course, but expect this to be about 3-5 years down the road and expect to pay >£1000 for one, even at 24". The manufacturing process simply isn't there yet for high volume mainstream level OLED, which would help subsidise the low-volume, enthusiast monitor market.