At least, my problem with blank notebooks, is never having anything to write down in them. I love the look at feel of premium notebooks and have shelves of all different types. I just found out I am not alone with this addiction when I found this site.
I am always so scared of starting a project in one, and then changing my mind and now I have this weird beginning in a premium notebook. This changed when I started working on the Startup Notebook. I filled a notebook to the hilt with ideas and sketches as I brainstormed day after day for months. Here are a couple pics from my notebook:
When I thought of this idea, I was traveling and only had access to a composition notebook, but it has served me well so far, and fits nicely in the folio I designed to keep everything handy.
The point I am randomly circling is that no matter what you prefer, start writing down all your ideas and get them in front of you so you can see them all. It helps make space in your short-term memory so you can go deeper into topics without worrying about forgetting the first set of ideas.
You will also find what you are passionate about when you have no trouble writing about it. Ideas will pour out of your head and if you stick with it long enough, you will have created something, or stumbled onto a new idea, but you need have a way to catch all your ideas to keep moving forward. So even if it is just a comp book, start writing things down.