I think there is a misunderstanding because the European proxies will mirror the WHOLE of the Wikimedia projects: all projects in all languages, not only some European languages. And because many European people also read and contribute to English projects, even if English is not their mother tongue.
That sounds excellent, but isn't that technically difficult? Maybe I've missed some discussion of how to do this.
It's easy to fix it so that fr, es, de, are all routed through the European squid proxies: we just point the dns entries at the new ip numbers for the French squid cluster, no problem.
It's much harder (right?) to identify where a user is coming from and route them through the proxy that's best for them. This is what Akamai and people like this charge big bucks for doing.
Or, is there a free (or cheap) way to approximate that?
--Jimbo