From those pictures it looks amazing. Honestly, I never even thought to use makeup to enhance cleavage... In any case, echoing concerns of others, it might not look as good in full on sunlight, especially if the makeup is too dark, though something tells me that you have an eye for makeup so I don't think it would be too dark.
I especially think that this would be a great tactic for clubbing, where the low light conditions make it difficult to stand out in the crowd, but I think if you went to the club looking like that, you would certainly be noticed in a totally good way.
Also echoing other comments, I really like that top as well. It is the sort of top that only looks right with a little cleavage so, it makes the effect that much more stunning. I have to admit: I am a bit envious right now