Beginning with OS X 10.4 (Tiger), Safari includes RSS reading features.
You can use NetNewsWire as your default RSS reader instead. This way, when you’re using Safari, you can easily subscribe to feeds in NetNewsWire just by clicking the RSS button or the link to the feed in Safari.
When you see an RSS button in Safari’s address bar, click on it to subscribe to the feed in NetNewsWire.
NetNewsWire will check that you want to subscribe to the feed. If you’ve already subscribed to it, NetNewsWire will select it in the subscriptions outline.
Similarly, when you click on a link to a feed in a web page, NetNewsWire will then ask if you want to subscribe or select the feed if you’ve already subscribed to it.
For instance, any time you see an orange XML button
or a Syndicate this Site link, just click on it to subscribe in NetNewsWire.