Philipp posted at some point that you can't add "todos" as a new Gmail label. The explanation was that todos means "all" in Spanish. But why can't you add "important"? I don't think it's a translation of an existing label (like "starred") in another language.

Some possible explanations come to mind (none too satisfying!):
- "important" may indeed be a word in some language, e.g. meaning important but for some reason chosen to express "starred" (perhaps because there was no fitting translation for "starred")
- labeling something as "important" is some upcoming feature for Gmail...
- Google has a "block list" for a couple of dozen words just in case they ever need them, and "important" coincidentally happens to be on it...

"important" is french but for stared mail gmail uses "suivi".

Speaking of labels, I've just realised how little I use them. When I first started using Gmail, I set-up lots and lots of filters for incoming mail to be labelled, but I've had to actually access my mail with them before. Search works for me everytime.

Does anyone else just use search instead of labels?

I don't use labels as keywords or tags, but I use a couple e.g. "tracker" for automated emails (I get an email with a post content whenever a Google blog posts something new).