if you want an RSS feeder for Safari, there are several extensions you can download which bring that function to safari...
you can also just do it in the Mail application in it's side bar instead... (any old RSS feed link in Safari if you click on it will give you that option)
the RSS feed, like flash, slows Safari and your machine down considerably.. in the mail app they are checked when the rest of your mail accounts are checked during it's auto refresh cycle...
http://www.macupdate.com/app/mac/44228/subscribe-to-feed-safari-extension
by the way, a useful hint about flash on safari, if you do download flash from adobe, keep your "acitivty monitor" application in your system tool bar, when you launch safari, and go to a webpage with a bunch of crappy flash adds, click on activity monitor, find the flash process that is running and kill it... suddenly your safari application is about 10 times more responsive for every website (that has flash adds) if you need to watch a video in flash, just relaunch Safari.. and there you have it, and then when done immediately kill the flash process again...
"activity monitor' can be found in your applications folder then under the utilities folder... (click on big stop icon after highlighting a process that is running)
apple is interested in improving the whole experience and that means removing old tech that is slowing things down, like flash and RSS, and replaceing them with new tech, if you want the old tech, Apple is just allowing those companies to write extensions, so you can get that function back. but you would be wise to try to not do that, and find the new tech...