g1smd - 8:49 pm on Mar 23, 2011 (gmt 0)

If you have many images, then some simple changes to your .htaccess file could make a big difference. There's several prior threads including [webmasterworld.com...] and [webmasterworld.com...] .

Please test these things out and add your comments both here and to the discussion at [core.trac.wordpress.org...] too.