[burntsushi]

It depends. There is a certain allure to working with a shiny new technology. It's sort of like an adventure, because not many have paved a strong path forward yet. But not everyone likes an adventure. Sometimes there will be huge roadblocks that don't have obvious solutions; especially for the beginner.

On the other hand, the scientific computing crowd for Python/NumPy is well established and there will be plenty of people who have probably come across any problem that you will see. There is already an established ecosystem of tools that you'll be able to draw from, and it's likely that many of them have been well tested and are reliable.

The decision is really up to you. Do you have the time and desire to go on adventure? If so, maybe Julia would be a nice pick. Are you short on time or weary of adventure? Then maybe Python/NumPy would be a better pick.