Well if you call it flying_sweatdrop, chances are someone down the line is going to apply to have it implicated to sweatdrop. It would be good to get a concrete explanation of their purpose to show people it's different. It seems to me almost as if they're a milder version of /\/\/\, although I still think they are sweatdrops. post #1006972 also has them.
They're nothing like /\/\/\. That's used for shock or surprise, a sharp moment when something is realized or noticed.
These sweatdrops are used more like a sign of being nervous or uneasy. The character Cyberia-Mix linked, Sakurai Izumi, has them at practically all times, being an extremely nervous and uneasy character.
It's pretty similar to sweatdrop, but it's visually distinct from it, which should probably qualify it for it's own tag. I don't think an implication to sweat drop would hurt much, though.
I think the realistic sweatdrop you see for example when a character is caught red handed doing something bad is somewhat closer to the purpose of the blue drop than sweat you get from heat, effort, fear, etc.