I am in the process of moving an entire site from ID based pages to user friendly / descriptive urls, and I would like to move the blogs as well.
My problem is then, that I am uncertain if 301 redirects will be enough to be completely covered, as I am not sure if all readers support these, and I do not want to loose any subscribers if I can help it.
For regular HTML pages there is the canonical "redirect", telling google and others, that the url is moved, but the old url is still valid, but I can not find a similar functionality for blogs. Does such a feature exist, or is 301 really going to work for all my subscribers? Alternatively, is duplicate content an issue for RSS feeds (not comparing to the site, but having multiple RSS feed links that really is the same content)?