We at Formations&Co, having researched this subject and having obtained information from various authorities such as FIDE, the office of population, state, project manager, etc. would summarize the most important implications of the directive as follows:
The disposition seems to be obligatory for non-EU nationals, but this should be double-checked with your local migration office.
Non-working spouses who arrive in Switzerland have one year in which to present a diploma certifying the attainment of an A1 oral level in the official language (French, German, and Italian) of the canton in which they are applying for or renewing their permit. Great care should be taken when considering the time needed to achieve certification. The process of taking an examination, receipt of diploma and its subsequent validation by FIDE involves time. It is recommended to assume 10 months for examination preparation to allow for these other steps.
This directive also applies to foreigners who have been in Switzerland for several years. A valid diploma is required at the time of the renewal of a permit.
In the event of family reunification, expatriates must prove that they have A1 oral level in the local language or that they have enrolled in a French, German or Italian course appropriate to the canton where the residence permit is delivered.
The main recognized examinations are the FIDE examination and international diplomas such as DELF (French), GOETHE (German) and CELI (Italian)
For your information, the state of Geneva estimates that more than 57,000 people will be affected by this directive!!