There weren't too many differences between the popular trends in Amsterdam and the trends here. The streets were saturated with leggings in every shade and pattern imaginable. My favorite were mustard yellow with a grey mini dress and black sued booties.
What I found most intriguing about Amsterdam were the bike riders. More of the population travels by bike than any other means, and this did nothing to deter women from wearing mini skirts and four inch stilettos with long scarves trailing behind them. All the things that I would never wear on a bike for fear of death and fashion disaster.
The heels were by far the most astonishing to me - I imagine the wear and tear on them must significantly increase - the scuff marks they must endure would kill me. And as far as I could tell, there was no such thing as a Payless, even shoe prices in second hand stores hovered around 35 euro.
Travel by bicycle did not prevent anyone who wanted to from dressing to the nines, nor did the rain. Riders simply steered one-handed while using the other to hold the umbrella.
Shopping in Amsterdam, for me, was not worth it. As the styles and shops (H&M was everywhere) were so similar I would just be paying 40% more for something that was made in china which I could easily buy at home.
Other than the lack of bargains, Amsterdam was a fun and beautiful city to have visited. Since everyone speaks English, it's easy to socialize with the natives (and there are a lot of really good looking natives which you would like to be socializing with). The city was clean and most of the cats were friendly, so I would definatly say that Amsterdam is a worthwhile place to visit.
Also, if you do go, even though it is still summer here and all your boots are packed in the far back of your closet, you must dig them out and pack them. All the cute sandals you want to bring will only leave your feet sad and cold.