I think there is another category at play here that I think of as contemporary. Seems to be that you can take just about any traditional quilt block and turn it modern by the use of color and pattern. Personally, straight up traditional quilts are not my cup of tea because I don't like the colors. But take that same block and play with new colors - give it some negative space and all of the sudden it's gotten pretty darn modern. Strictly modern quilts, as someone else has noted, are more like art quilts - no pattern, just your own creative ability at work - very often does not fit into a handy block format. Modern is what peaked my interest and keeps me spending money all over the place for fabric and supplies.