(No, really. The French media is being shrill and the French government is being silly, over the prospect of a possible takeover bid. Newspapers have been giving this front page coverage, mind you.)
John Rosenthal, writing at Transatlantic Intelligencer, takes a look at the situation here. In his second update, he provides a link to The Yoghurt War at EURSOC, which has good background on the story. Notably, it was not that long ago that Danone was being held up to scorn in France.
There are other factors to bear in mind. From The Yoghurt War:
...The reported takeover is still nothing more than a rumour: Some PepsiCo officials appear bewildered by the storm, while other insiders claim that Danone is blowing up the rumours itself to provoke a "rescue bid" by a rival firm like Nestlé. Nevertheless, Dominique de Villepin has telephoned Danone's chief executive Franck Riboud to assure him that the government will do everything to help the company fend off unwanted advances.Who knew that a "no" vote on the EU "constitution" would shake something like this loose? ;-)
But what can the French government do? Legislation exists to prevent hostile takeovers of companies identifed as crucial to the national interest - utilities, even, at a stretch, certain manufacturers. Governments opposed to foreign ownership of certain politically sensitive "national champions" stretch these laws on occasion. Last year, France's government fended off a takeover of a French pharmaceutical firm, claiming that the company made drugs that might be required to protect citizens in the event of an al-Qaeda biological attack.
Even a government as slippery as this one would have difficulty stretching national interest laws to take in a biscuit and yoghurt manufacturer.
However, the fact that the government is interfering at all indicates its jumpiness. Following France's rejection of the EU constitution - blamed by France's elites on opposition to globalisation - discussion of national champions and state protection is no longer taboo. But governments cannot appear too anti-business, even if citizens lap up populist postures: If investors are scared off, the impact on French jobs could be a great deal worse than any loss of face because of Danone's takeover...
Update: Mr. Rosenthal has a follow-up post, with timeline.