I love the vintage side of Gucci's image, the Studio 54 party girl vibe, so I like the way these pictures try to play on that. The drawbacks are that the bottle is simply too big, it looks like the girls are straining to keep it held up, which adds a sense of stress into the image, instead of insouciance.
Also, the date of the dresses doesn't bother me so much, though if they were truly going for a vintage vibe, they should have capitalised on their history, and had them wearing modern updates of something from decades ago.
The monotone colour scheme to me is a visual attempt to emphasis the 'feel' of the scent. The tone on tone is saying that the scent is rich and lasting, drowning in something deep and autumnal. If they'd used lots of different colours, I'd have formed a different mental image of the perfume - I'd have felt it was lighter, less substantial. The colour overload is designed to speak to a different sense then just the eye.