I think that etehreum is more being used than bitcoin as we are seeing so many ICO based projects that are constancy being released and that shows how much development and how much ethereum can bring the blockchain technology to various fields, and for that i think that over time etehreum will surely become a strong candidate or bitcoin, but never surpassing it because bitcoin is the first of its kind it is like gold it never loses its value and everyone and whatever happens people are always going to support it.
most ICOs rely more on ethereum than bitcoin because ethereum has faster network blocks and much lower transaction costs than bitcoin. However, ethereum would not dare to take the bitcoin position because bitcoin has a much higher popularity and is already believed from its initial launch by investors because it has valuable asset value for long periods of time