Hi Threthings, of course you can do that. Not only to FB and twitter, you can automatically post your links to more than 40 social networking site.
Great isn't it?
Here is what you want to do:
1. Go to ping.fm and create a new account there. Ping.fm is a website that allows you to post to more than 40 social networking site in just ONE CLICK of a button.
2. After logging in, you should see your dashboard now. Look for "ADD NEW NETWORKS" link. Click it and you will see a bunch of social networking sites where you can create an account. You can choose which site you want to use or you can just choose them all. The more you choose the better. Be patient, it takes huge work and times but when you finish with it. you will have a very powerful networking method working automatically for you.
3. When you add a network, you will see that Ping.fm gives you options STATUS UPDATES or MICROBLOGING UPDATES, I suggest just choose both.
4. After you have registered with all that sites, you should try to PUBLISH something. Go to your main dashboard and you will see a big text box where you can type something in. Just type anything you want, "This is my first post", "Testing", or anything. Then click PING.
Now you have a very powerful tool to publish your content with a single click of a button. Next thing to do is to synchronize your RSS to that Ping.fm site so when you publish new post from your blog, Ping.fm will automatically publish your link to all the social sites.
5. Go to //twitterfeed.com/users/new where you can register for a new account (again, it's free).
6. Log in yo your dashboard and look for "CREATE NEW FEED" at the right corner.
7. Click "SHOW MORE SERVICE" and select PING.FM. Make sure you are still logged in to your ping.fm account.
8. Twitterfeed will ask for ping.fm key. you can find your key at //ping.fm/key.
9. Type in you key and click "GET AVAILABLE METHODS" then choose "MICROBLOG" or "STATUS". I suggest you to choose "MICROBLOG". "Click CONTINUE to STEP 2"
10. Fill in your feed name (it's up to you) and your RSS feed URL. Then click "TEST RSS FEED". After that you click "UPDATE FEED".
11. What's the next step? That's it. Just go publish your post from you blog. Now everytime you publish a post, your post link will be published to more than 40 social networking sites.
Good luck, All the best.
Ahmad