Under France's new tax laws, DRMed ebooks will be taxed at a higher rate (currently 19.6%), while DRM-free ebooks will be taxed at the lower 5.5% rate.
As I am sure many already know, ebooks are already sold in France with a 5.5% VAT, or value added tax, bundled into the list price. Technically that is illegal under current EU regulation; ebooks are defined as a service and thus should have a higher VAT applied. But no penalty has been applied (so far) so at this point it is really a matter of opinion.
And just to add extra confusion to the matter, EU tax law will itself be changing in 2015, and under the new rules ebooks will be taxed at the lower rate (the one that France is not supposed to be charging right now). The new EU tax laws will also require retailers to collect taxes based on the customer's location and not based on where the retailer is based.
As you can imagine, this is going to close the Luxembourg tax loophole enjoyed by Amazon, Kobo, and a lot of other ebook retailers, but just as importantly this new tax law will create an opportunity for France to penalize the sale of DRMed ebooks.
DRMed ebooks will cost more - theoretically. Speaking as someone who has long been an advocate of DRM-free, I think this is great news, although I'm not sure how much of an effect it will have.
Given that ebook prices vary wildly based on market, publisher, popularity, and sales status, I'm not sure that anyone will notice the difference. Also, France is one of the countries with a fixed price law for books (and ebooks), which further complicates the pricing situation.
There has been a growing movement among French and other European publishers to go DRM-free, and this will likely inspire some to make the switch. But a good part of the French book market is controlled by major publishers who could be immune to the financial pressure.
On a related note, I have to say that I wish they had thought to include audiobooks as well. They could have deDRMed that market as well. It might be relatively tiny at the moment but that's no reason not to apply the same tax laws to it.
What little info I have on the French ebook market says that it is a 3 way race between Amazon, Kobo, and Apple, with Amazon slightly in the lead.