I get this, too. It doesn't bother me too much because I know it's probably the malware I reported before, just a bit less conspicuous. A few times, I try to do something like log a food in fitday and I get flashing error messages that seem to match the typeface and typesize of this annoying malware.
It is definitely a problem. I have several two products running on my computer and they both address malware. Prevx and the Microsoft Security Essentials product. They both have been reliable - and actively scan, looking for 'bad guys.' I believe this is a variation of the awful malware that popped up here in the past (it doesn't show up anywhere else in my computer - this is a fitday specific thing). Other people experienced this in the past, the fitday administrators tried to address it. It's back, in a slightly different form.