[Giroflex]

Never had any trouble with `pip install --upgrade library`.

Not sure if there's support for upgrading all packages at once, though.

[ekianjo]

There is no such support for multiple packages at once. R can do it though.

[scaryclam]

You can certainly update multiple packages at once using pip. Just use a requirements.txt file, which you should be doing anyway if you're using multiple packages (or just want to be able to reproduce your environment).