1. The only other program that has RSS like Safari is Internet Explorer 7. OmniWeb doesn't do true RSS displaying, but it does keep track of the feeds and tell you when they're updated. Also, and as I've been told here, Atom feeds have never worked.
2. There's always
ShapeShifter.
3. In the default settings, you probably have the bookmarks set to check every day. You can set this to every day, hour, or week. You can set this by going through the options on the bookmarks you want to update.