As far as readers that integrate into your browser, I would have to say the
Sage extension for Firefox is about the best.
Major Features:
* Reads RSS (2.0, 1.0, 0.9x) and Atom feeds
* Feed Discovery
* Integrates with Firefox's bookmark storage and Live Bookmarks
* Imports and exports OPML feed lists
* Newspaper feed rendering customizable via style sheets
* Technorati and RSS search engine integration
* Catalan, Chinese, Dutch, French, German, Hungarian, Italian, Japanese, Korean, Russian, Spanish and Swedish locale support
* Simple, one step install / uninstall
After installation, there are four ways to access Sage in Firefox:
* Menu selection, Tools -> Sage
* Menu selection, View -> Sidebar -> Sage
* Keyboard shortcut, Alt-S
* Toolbar button, View -> Toolbars -> Customize, drag the Sage icon to the toolbar