I recently read this interesting post on the NY Times blog "freakonomics" titled:
How The Market Influences Which Language You Read In"
http://freakonomics.blogs.nytimes.com/2009/07/02/how-the-market-influences-what-language-you-read-in/
The article mentions how people in the Netherlands would rather read the English translation of a Swedish book than read the Dutch translation.
The reason for this is that there are many more Swedish to English translators than there are Swedish to Dutch translators.
Meaning the Dutch translations generally have more errors than the English translations.
The Dutch people say they'd rather read a proper English translation than an error-filled poorly translated Dutch translation.
If you take this to it's logical conclusion, you will realize that many Europeans in "smaller markets" are already, in some small ways, choosing English over their own language.
Which then means that... eventually... most European people will adopt a more popular language than their own, merely for the sake of convenience.
As languages like Dutch, Swedish, Kashubian etc. fade slowly away, more and more people will gravitate toward English, French, Spanish, and German.
Eventually, over time, English, French, Spanish, and German will be the only languages spoken in Europe.
Over, even more time, these 4 languages will likely blend into one language spoken by all people in Europe, Australia, North and South America.
Over even more time, Chinese, Korean, and Japanese will also merge.
So the good news for people 200 years from now is that there will only be two languages to learn in order to speak to everyone on the planet. European (Spanglish-Franco-Germanic) and Asian (Chinese-Korean-Japanese).
[doesn't really affect us just yet]