White is just like any other solid color, I think. I have several yards of it, but I also have loads of green, blue, light blue, peach, red and tan solids. I'll probably be digging out the white here shortly for a baby quilt but I haven't really needed it for a while.
As others have said, let your first few projects guide you - unless you see a mamma-jamma sale on white. Then go nuts!