Interesting discussion.
I am American and the way MFL is taught there can be godawful/nonexistant to very good depending on the school district you are in and what kind of university you went to. I went to a very good school and a top Liberal Arts uni. French started from early primary, simple things until sixth grade (Year 7) when we started to be formally taught. It was a combination of culture (first week, we learned about the history of the major Chateaux in the Loire valley), vocal and grammar. We had to take French until 10th Grade (Year 11). If you dropped French, it was because you had started Spanish in 9th Grade (Year 10) and would continue that until graduation in 12th Grade. Latin was also started in 8th grade and could be continued until graduation. A minimum of one language needed to be taken throughout school.
I stuck with French, and by the time I was in 11th Grade, we were reading, discussing, and writing essays in French on some of the great works of French literature (Moilere, Voltaire, Racine, Rimbaud, Baudelaire, Sartre, Camus, Hugo, Mauriac...). There is no mandatory national examination so each school could tailer the way they taught the language to their student population - I guess my school was quite academic and I think most of the posters here would have hated this kind of teaching.
In uni, you had to continue MFLs for at least 2 years as part of the graduation requirement. IN addition, many students spent their Junior year (third out of 4 years) in total or partially abroad. I had friends start learning Mandarin in their first year, spend their third year in China, and be very comfortable speaking and writing it by graduation.
Professionally, I should have learned Spanish. I trained in medicine in California and a very significant portion of the population I was treating was Spanish only speaking and, although I picked up a workable vocabulary in critical terms, I relied on my nurses and co-workers who were spanish speaking. French did not help me because although I could write and pass oral exams on French lit and art, I didn't know the necessary medical vocabulary so I couldn't try and teach similar words.
I agree with many posters who think that learning an additional language is important for a well rounded education - however I also understand that, to a sizeable percentage of the population, it, along with art including history/music/drama are a frivolity. Perhaps part of the problem is the focus on exams and qualifications which education in this country has. Perhaps there would be greater focus on the pleasure of learning these subjects is obtaining A levels or O levels was not the end goal?