i recently completed a freebie pattern marked "confident beginner" from the robert kaufman website.
the directions were not at all well written and if you were a quilter with two or three quilts under your belt, you might find them very confusing. it also has a number of matched seams cut on the bias that were pretty tricky.
i did a variation of a pinwheel quilt from a mcall's magazine that was rated intermediate (i think) and upon completion i would definitely have rated it advanced.
i think it comes down to individual skill and experience, but anything with angles, tricky seam matching, bias cuts suggest at least intermediate to me.
aileen