Tweetdeck replacement for Mac Is there a Tweetdeck replacement for mac? A program that'll allow me to post to both my Twitter account and Facebook accounts with a single action?
Try HootSuite. If you want it to become a desktop app, use this.

Otherwise, you can use the official Twitter client and configure the Twitter Facebook App to post your twitter updates on facebook.

You can also use Google Chrome and Mozilla's Prism (as a extension in the browser or as a standalone) to do the same thing.