Here's a new port of R's ggplot2 over to python. Looks very slick!
https://github.com/yhat/ggplot/
More info here:
http://blog.yhathq.com/posts/ggplot-for-python.html
Also have a look at Seaborn, described as "Improved matplotlib for statistical data visualization":
https://github.com/mwaskom/seaborn
The Seaborn examples are pretty slick:
Plotting Complex Linear Models
Visualization Distributions
Time Series Visualizations