Currently eZ Publish is supposed to just use a maximum of one virtual host to serve content. As also described in http://developer.yahoo.com/performance/rules.html this does not support performance in the best way. Therefore we should think about support for splitting content delivery across several domains. Especially all the stuff having a rewrite rule in the virtual host could be "moved" to a dedicated (static) host which also does not required PHP or session which will additionally speed up the requests.
As a consequence the ezimage, ezdesign and perhaps also ezroot and ezurl template operators should be modified in a way that not only "full" is an option but also "full_static" which will use full URL with a different (predefined) host / domain name (to avoid cookie transfers it makes sense to use a different domain, too). In the optimum one would integrate a rotation within a set of hosts. The same should be supported by ezjscore.
We already make use of such kind of solution and can serve more detailed in information.
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