RSS Feeds Are Still Copyright Protected
I think commercial sites that want to consume commercial RSS feeds need to be aware of a company's “terms of use” policy. For instance if I'm a software vendor or run a commercial content site and I want to add some quick C# content, I can't just plug the C# Team's RSS blog feed into my site.
In theory, at least, I am still bound to Microsoft's TOS policy, which says:
PERSONAL AND NON-COMMERCIAL USE LIMITATION.
Unless otherwise specified, the Services are for your personal and non-commercial use. You may not modify, copy, distribute, transmit, display, perform, reproduce, publish, license, create derivative works from, transfer, or sell any information, software, products or services obtained from the Services.
Before consuming an RSS feed on a commercial site it is probably a good idea to get the permission of the content's owner. Otherwise, you may be guilty of copyright violations.