You can go to the same link you posted and read what I said is true... though admittedly, I did get the numbers slightly wrong. You, on the other hand, eliminated the most important part of the quote.
"...more than 40% of the samples [or ejuice tested] had higher than safety levels. Of note, the highest amount of diacetyl found was 495 times higher than safety limits, while for acetyl propionyl it was 22 times higher. tobacco cigarettes smoke contains both compounds, at levels 100 times higher for diacetyl and 10 times higher for acetyl propionyl compared to e-cigarette average daily exposure."
So let me rephrase...
Yes, I know diacetyl was in the cigarettes I smoked, but when a study comes out that says it was found in some efluid in the magnitude of 400+ times more than the safety limits -- 400% higher than tobacco cigarettes -- in fluid of which some were claiming to be diacetyl-free... well, I think a reaction of concern on my part falls in line with something more warranted than ridiculous.
Also, Dr. Farsalinos who is the author of the study, he said right on the same page in comments:
"Many liquids with diacetyl came from vendors who specifically and clearly mentioned in their websites that all products are diacetyl-free. Thus, only proper testing and presentation of the testing report will ensure that these products are indeed free from these chemicals."
The whole point was that if someone saw your post and repeated it. It happens you know. So it is incumbent for use to get the facts right, unlike the people who are attempting to ban or severely limit ecigarettes, who have been as blatantly sloppy with the facts. And as far as vendors - 'many' doesn't equal 'most'. And also the 'highest amount' of 495 times safe amounts could have only been one tested - not every eliquid or even most.
Again, if you're concerned about diacetyl, the do what is necessary for you to be what you consider to be safe. But don't skew the facts, in order to overly justify your own decision.