According to the Journal officiel of the French Ministry of Culture for 20 mai 2005 (NOR CTNX0508288K), La Commission générale de terminologie et de néologie has determined that the correct French word for blog is "bloc-notes". If you want a shorter form, you should use "bloc".
The compound term bloc-notes is an old one, whose meaning strikes me as rather inappropriate as a basis for extension to blogging. It's cited in the 1932-35 DAF as a "terme de Papeterie" with the gloss
Feuillets de papier de même format légèrement collés ensemble sur un seul côté, de manière que l'on puisse les détacher facilement un à un pour prendre des notes ou écrire des lettres.
Leaves of paper of the same format lightly stuck together on a single side, so that one can detach them easily one at a time in order to take notes or write letters.
This is what we would call a "writing tablet" or a "pad of paper", I think. Somehow I don't think that the tabletosphere is going to take off, terminologically speaking, or the padosphere either.
The short form, bloc, basically means "block", but in sound it's curiously similar to "blog" -- you just have to change the final consonant from a voiced velar stop /g/ to a voiceless velar stop /k/.
So, it seems, that the official French word for blog is now just "blog" pronounced as a German would, with final devoicing. Several witticisms come to mind, but I'll restrain myself, at least temporarily.
However, I can't resist quoting Mahalanobis on the response from Brussels:
In Brussels, the EU Ministry of Technologie reacted with alarm to this proliferation of 'blog' terms unique to each country, especially after they learned that the Poles intended to call them gzybrgrlz. The EU has consequently appointed a commission to draft a plan to hold a meeting to prepare an agenda. Officials are hopeful that a single, Europe-wide standard term can be introduced in time for the 2104 Olympics.
Because this remark preceded the French electoral defeat of the new EU constitution, the situation is now more complex, perhaps requiring a preparatory committee to decide on the methodology for establishing priorities for the commission drafting the plan for the meeting to set the agenda.
[Update: Jean Véronis has written a wonderful essay on this subject, entitled Lexique: A bloc contre les blogs!. He observes that
nos lexicographes officiels ont oublié un petit détail : on a besoin d'un nom et d'un verbe dérivés. Les bloqueurs vont-ils bloquer ? C'est un peu bloquant...
...our official lexicographers have forgotten one little detail: we need both a noun and a derived verb. Are "blockers" supposed to "block"? It's a bit "blocked up"...
Jean also quotes Montaigne about the nature of language:
"Il escoule touts les jours de nos mains : et depuis que je vis, s'est alteré de moitié. Nous disons, qu'il est à cette heure parfaict. Autant en dict du sien, chasque siecle."
It slips from our hands every day: and during my lifetime, half of it has changed. We say that it is now perfect. Each century says the same.
And Stefan Tilkov points out by email that "one of the meanings of the German word 'Block' actually is 'Leaves of paper of the same format lightly stuck together on a single side, so that one can detach them easily one at a time in order to take notes or write letters'". ]Posted by Mark Liberman at June 3, 2005 10:40 AM