Like the others had said: DoctorJS (formerly jsctags) is the best option.

However, integrating it with Vim by writing custom wrappers or using Vim-taglist-plus plugin, which isn’t currently working, aren’t good solutions.

The easiest way I’ve found is to install the TagBar Vim plugin (NOTE: It’s TagBar, not the old infamous TagList!).

See my other answer for more info.

Edit:

There’s a new project called tern.js which should replace the dead doctor.js. See the link above for more info.