The most efficient method is to follow American blogs and forums.
The newest info and most interesting articles are often posted across the Atlantic.
In France, here are two websites offering almost every day the best of SEO news :
- fr : Manual monitoring FR + US + UK
- com : Manual monitoring FR
There are a lot of blogs, too.
In English, here is a list of more than 400 sources:
In French, you will find a list here: