The first time I smelled this, I found it really appealing. There's just something about it that makes safe and likeable, which I still wonder about. Then, I tried other things, forgot about it, dismissed it. As my tastes grew, I called it cheap, common, used the word "aquatic" and put it out of my mind for a few years. That is until recently... when I revisited it, tried it with an open mind, and surprisingly... it was still appealing! It actually feels like lying on an Italian beach, after a swim in the Mediterranean on a hot day in summer.
To start off, I can understand it's popularity, but I'm going to try and focus on why it's popular. Aqua di Gio is the fragrance which started the aquatic trend of the late 90's and which continues to the present day. Put simply... it was a landmark in that field, and spawned countless imitations, very much like Davidoff's Cool Water did 8 years previously. To me this fragrance does not smell as cheap or as cliché as other people make it out to be. It is popular for a reason, and just because it's common doesn't mean it smells any less good.
If I just focus on it's smell, not it's reputation, I would say that it reminds me of the beach under the hot Mediterranean sun. I really think the advertising fits the fragrance perfectly. I get salt water, hits of peach, jasmine and musk. In fact, when I close my eyes I get the impression of a basket of peaches and herbs and flowers all drenched in seawater and left drying in the sun. I don't know why, but that smells fantastic on skin!
I think I know why this is so appealing to many people. Personally I think it's to do with the salty watery vibe it gives off, coupled with flowers and sweet musk. It smells like warm skin, like you just stepped out of the sea (note: this smells nothing like a swimming pool... for those of you talking about calone etc.). To me it gives off a sweet smell of sweat, mixed with sea water and a jasmine floral musk type vibe. In short, it's like stepping out of the sea on a beach in Southern Italy, that's what I get out of it.
Having said that, it's very common and I can only see this working in certain situations, namely summer (especially hot summer days, I think it would do amazingly well then), any situation which involves swimming (beach, pool, vacations), I think it's perfect for a summer holiday by the beach; and finally I find it works best in casual situations, definitely a t-shirt and jeans type scent. Maybe a white or light coloured shirt but never a suit.
Yes it's common, a best-seller worldwide, but in the right type of situation (beach holidays, swimming, t-shirt casual), it works amazingly well. Summer Classic!
Edit: If you're interested in the "Essenza" version released in 2012, I couldn't find much difference between the two just that the eau de parfum focuses more on the woody and floral aspects of the original and less on the aquatic, fresh citrus side.