The yield curve has been relatively stable at close to 0. Indeed (as I understand it) that's the entire point of quantitive easing: it artificially keeps interest rates on long term securities down to encourage that money to be lent and spent http://marketrealist.com/2014/03/fed-taper-quantitative-easi....
The short term rate is 0. The yield curve is the curve if you plot interest rates on the y axis, and length of treasury bond on the x axis. This creates a curve that tells you what investors think will happen to the interest rate over the next 3 months to 30 years.