matplotlib doesnt' work the first time.

In 0.8.0, with ipython, a script like

import matplotlib
import matplotlib.pyplot as plt

plt.figure()
x = [1,2,3,4,5,6,7,8]
y = [20,21,20.5,20.81,20.0,21.48,22.0,21.89]
plt.plot(x, y, linestyle='dashed', marker='o', color='red')

The first time you run it, it prints [<matplotlib.lines.Line2D object at 0x7f02c22946a0>], but no actual output. If you try again, it works. This seems repeatable.