1) Atom has separate <updated> and <published> fields, while RSS just has <pubDate>. Moreover, RSS wants to you add a redundant day of the week in the date, i.e., "Sat, 07 Sep 2002 0:00:01 GMT", which is dumb.
2) Atom allows you to use <content type="html"><![CDATA[]]></content> where you can just stick in HTML, whereas RSS <description> just specifies "entity-encoded HTML is allowed".
3) RSS has redundant <guid isPermaLink="true"> vs. <link>. Which one is a feed reader supposed to use?
Is it really bifurcated for the end user though? Its the same tooling to view both feeds. The same workflow to add either feed to your feed reader. You don't even realize whether its an atom or rss feed unless you start looking into it.
> Is it really bifurcated for the end user though?
Yes. Suppose you are build feeds search engine. User enters query that matches some blog. This blog exposes both RSS and ATOM feeds (very common scenario). Which one should your engine show in the results? If it shows both, which one the user should select for reading? And what if they differ, but only slightly? Why should the user be exposed to that?
Who's relying on one, who's relying on the other? Dunno! I guess we'll support both, because we're good Internet citizens that believe that breaking links is the absolute worst thing you can do.
As a consumer, I don't really have any preference. Both work fine with my software. My personal blog uses Atom only because my static site generator had an Atom plugin.
The rss pubdate format is the date time spec from rfc822 for email so is very widely supported. Cdata is supported in rss too — it’s in the xml spec so would be a bit redundant for rss to explicitly support it. You’ll find it in description elements very very often. I never understood why a link would not be a guid but the difference seems clear enough - use guid if you need a guaranteed unique idea and use link if you need a url to the list.
1) Atom has separate <updated> and <published> fields, while RSS just has <pubDate>. Moreover, RSS wants to you add a redundant day of the week in the date, i.e., "Sat, 07 Sep 2002 0:00:01 GMT", which is dumb.
2) Atom allows you to use <content type="html"><![CDATA[]]></content> where you can just stick in HTML, whereas RSS <description> just specifies "entity-encoded HTML is allowed".
3) RSS has redundant <guid isPermaLink="true"> vs. <link>. Which one is a feed reader supposed to use?