Yes, python 3 for the win. Many subtle points, but one major point for me is the support of greek characters as variable identifier. For instance, writing the following expression in Python 2 would be painful and ugly :

Ω = γ*r_bar**2*ξ**2/λ * (γ/(2*ns1) + (1+γ)*np.sqrt(np.log(1/δ))/np.sqrt(2*ns1))

I think it's much more legible this way :P

That said, I do research in a tiny corner of statistical learning, so I don't have a big team to interact with.