Solr redundant-write solution

This patch allows ezfind to update a list of solr instances at once, so this is basically a distributed-write-to-solr modification.
could do with $result = $result && $httpRequest ?
Side note 1: could you think of any case where having at least 1 write succeeding should be considered ok?
Side note 2: would it be possible to go for curl_multi to make the process speedier by having parallel requests?