I think that if you had close up more to the bubbles, it will be more aproperate to define it at Macro/Close-up.
Oso, the reflections off the bubbles would make it better.
The background (the spoon) give a very ugly contrast to the subject (the bubbles). If it is just the bubbles in the cup(whatever it is) and have the reflection of the spoon in the bubbles, I think it will make a superd pic!
It is not saliva, I think saliva would have stickiness to it ;p
Personally I thought the reflection on the spoon was distracting. I was exploring the curves - ovals of the cup and spoon and circles of the bubbles. Didn't think of doing a macro shot of the bubbles alone... will explore that when I have the chance again!
Also, wanted to explore the range of greys... without the spoon I think I wouldn't have noticed the picture or want to take the bubbles. So the spoon is an integral part of the picture I saw after finishing the cup of cornflakes and milk.