At first I was skeptical of this “engineering toy for girls”, but its creator—Debbie Sterling, a Stanford-educated engineer—seems to be taking the problem of appealing to gender stereotypes pretty seriously.
We need to keep in mind, by the time they’ve reached the age of five (the youngest age GoldieBlox is recommended for), many girls will already have well developed gender identities, and oftentimes that identity will be quite, for lack of a better word, girly.
The Kickstarter project has a great video that explains more.