I think this top is just stunning! It would look gorgeous with jeans, layered under a nice jacket, or dressed up for going out. The ribbing pattern has a lot of sideways stretch and the top is meant to be worn very close to the body. If you prefer a looser fit, you might want to go up a size - just check the finished measurements for the size you want to make.
The yarn I used works up at a gauge of 5 sts per inch in Stockinette stitch, but it would probably also work at up to 6 sts per inch, so it's on the light end of worsted; if you wish to use a different yarn, make sure you find one that will match this gauge.
28 sts and 30 rows = 4" (10 cm) in Ribbed Openwork Pattern