I have long pondered this question and have come to some conclusions on my own. RSS is powerful and very light on bandwidth usage. Aggregation is very effective, simple to use and can be used to gather tons of information with very little processing power and bandwidth. However, there are some weaknesses of RSS which come to mind.
RSS is a text based protocol and the design of the site, the aesthetics and the overall experience is muted. Visiting this site and browsing the various features and comments (etc.) cannot be replaced by an RSS feed. I personally use RSS to see if there is any new and relevant information on a blog or site that I frequent and then I visit the site to check it out for myself. So RSS, for me is more about prospecting than it is about aggregating. Many of the newer mutlimedia blogs are completely lost to RSS. For example, the experience of visiting and browsing a picture blog is reduced to a bunch of pictures (if the feed is setup correctly) where the context and the design of the site do not play any part in the experience. The overall experience of writing and reading a blog is diminished. This thought has been expressed many times by Matt, Zeldman and others. But I think this is not stressed enough.
There are just way too many undecided news feed protocols out there. Dave Winer and others have tried very hard to come up with strict protocol definitions but have failed in many ways (in my opinion of course). The various versions of RSS, RDF, REST and now ATOM are way too difficult to comprehend, keep up with and fashion to the liking of your blog. The specifications need to be frozen in order for implementation to be absolute. In writing some code for these feeds, I have also found that the specifications are very fragmented and quite difficult to adhere to. It almost feels like they have been put together with only a certain peice of software in mind and interoperability is an afterthought rather than a primary goal. It is also very difficult to understand the difference in features of the various protocols.
In coming back to the topic of this post, I would say that publishing news feeds on a blog or CMS is a good idea but it should not become the sole method of visiting blogs. Blogs are designed to be read through the interface designed for them by the author. Each blog has a lot of personality and a lot of user experience is associated with browsing. I suggest that you offer one or two kinds of feeds through your blog interface and ignore the rest. As for the readers of a blog, I suggest that you visit the blog rather than just reading their news feed everyday. Not too many authors update their blogs everyday and a couple of visits a week should satisfy even the most avid follower. Just visit your list of blogs once in a while and click around, you will be pleasantly surprised.