[chingjun]

The problem with using the English message as the key is that, when we changed the English text, we'd have to change the keys in all other languages as well. Also, the same English text might translate to different texts in a foreign language depending on the context / location appeared.

Disclaimer: I've never used gettext before.

[earlyriser]

And also sometimes a key id is fine because you can add some context in the key like login_welcome signup_welcome. You can also use for grouping strings belonging to the same section: login_welcome, login_callToAction