Ah, more thoughts on how topology should be set up.
French squids would have such cache-peer configuration:
Cache_peer frsquid1 sibling 80 3130 proxy-only no-digest no-netdb-exchange Cache_peer frsquid2 sibling 80 3130 proxy-only no-digest no-netdb-exchange ... Cache_peer usasquid1 parent 80 3130 round-robin no-query no-digest no-netdb-exchange Cache_peer usasquid2 parent 80 3130 round-robin no-query no-digest no-netdb-exchange Cache_peer usasquid3 parent 80 3130 round-robin no-query no-digest no-netdb-exchange ...
The trouble with .paris. (or .tier2. or whatever) subdomain is that it would require either adding rewrite rules on Wikimedia servers, or it will require external rewrite agent on squids. I guess rewriting on Apache is much easier at this point.
Moreover. Florida setup should have 'Purge' service for recursive purges from all official squid caches (there might be more of those in future). Volunteers for that? :) Ok ;-)
And sure, object expiry timeouts could be reviewed here.
Domas