certainly true, though you must temper that with the fact that HFCS forms a very small fraction of the volume of a drink/snack, serving to dilute the potential mercury to an extraordinarily small amount per drink/snack.
About.com[1] says a soda contains 23 grams of HFCS, and a there are about 226 grams of soda in an 8-oz can[2], so HFCS makes up about 10% of a soda (wow!).
From the worst of the tested sources, in this survey, a soda could contain .06ppm mercury, more than an order of magnitude smaller than what the government considers dangerous in seafood.
It's interesting to read about Jeremy Pivens' mercury toxicity[3]. In order to reach a point where it affected his ability to live life normally, he had to eat sushi twice a day, every day. Furthermore, his doctors said that a few months of treatment would solve his problem.
It seems likely to me that the amount of HFCS you'd need to eat in the very unlikely worst case to get actual mercury poisoning is going to give you diabetes before the mercury affects you.
Which is not to say that we shouldn't stop allowing people to sell mercury laden HFCS! If 9/20 studied samples contain no mercury, they all should, it's clearly a public health problem. What I mean to say is just that this is likely only to be a serious problem for a very few very heavy HFCS consumers, if any, and that people shouldn't take it to mean "I can't eat HFCS because I'll get mercury in me", because they probably won't get clinical amounts of mercury.
There's plenty of good reasons to avoid HFCS, I advocate that to everyone, but I don't think that the fear of the mercury found by this study is one of them.
