No, I definetly don't think English words will invade the French language that much. Especially not casual words such as 'mettre' or 'café'!
Perhap's some newly invented words will be borrowed, as it has be done with 'internet', 'web' or stuff like that.
Mais l'Anglais ne peut pas carrément remplacer le langage courrant!
You did not read my post carefully then! I said that MIGHT happen; and even then, that was just illustrating my point that languages are going to be caught up in the influence of English.
Yes, I should have said another language that is already under the powers of English (Gaelic or Breton under the power of French), but my view still stays the same. In 500 years time, there are going to be very few languages compared to what there are today.
Just wanted to say that many (well, not really many, but a fair number) English words used in French now are ancient French forgotten words, that crossed the Channel and just come back, slightly modified by a nice stay in Britain.
The annoying thing is when those words don't have the signification they should have (or had in the past).
This is not clear at all, sorry about that.