This nail polish colour, poetically named "Rock the Boat", is on the Essie website described as "shimmering french blue". It is the one colour that I bought from the summer 2013 Essie collection, even though I could happily live with "Naughty Nautical" as well :). The colours from this collection have a subtle shimmer in them, which is visible in the bottle, but not as much on the nails - you can tell it's there only when looking at your nails in the direct sun.
This shade of blue, which is quite close to lilac, is wearable also for those, who are not big fans of blue on nails.
It's been three days since I applied it and it is still chip-free, so quality-wise it is getting two thumbs up from moi (you know, since the blue is allegedly french ;).
... and a couple of pictures to prove the awesomeness of the colour :):