Loic has announced the opening of the registration for Les Blogs 3. It is on in Paris on Dec 11th and 12th, and costs €300 (excl VAT) if you register before November 11th.
The event has been renamed Le Web 3 to better reflect the broader focus on Live Web applications and not just Blogs this year.
Le Web 3 has its own website and you can register to attend online.
Having attended last years Les Blogs 2, I can strongly recommend attending Le Web 3.