encyclo - 4:32 pm on Oct 5, 2009 (gmt 0) You can use
There shouldn't be any significant difference between using a subdomain or a new domain, providing that the resource is on a separate server from the main site. If the new domain is pointing to the same server / document root, then yes you're likely to run into duplicate-content problems.
images.example.com and either use an A record or CNAME - but the details depend on how you set up your image server.
You can use