As someone who routinely uses python, R, and matlab for data analysis, I am going to have to give this a try. Matplotlib can be cumbersome and I am always looking for alternatives. This looks great! Can't wait to try it.
I currently use RStudio server to do analysis from the RStudio IDE in my browser- while all the client-sensitive data and computation happens in a remote box. Allows me to play with graphs on my browser as well,.
It looks like Plotly's advantage is in sharing the plots easily.
The advantage of using it in a browser: it's not on my local machine! So if I run some godawful super-intensive script, my machine doesn't slow to a crawl. Also, I work with client sensitive data and we try not to hold any on our local laptops. It's really a nice solution. Now if only they supported multiple monitors...
Here is the repo/tutorial for plotting with vincent https://github.com/wrobstory/vincent
[Note that vincent works great if you are using pandas for your data analysis.]