Installing the above Apps will also install the corresponding widgets for your home screen (LinkedIn doesn't seem to have one yet, tsk tsk), so you can begin with laying them out on your home screen right after installation. Here is how I laid it out - and again, this is just what works for me – so you should rearrange it according to your social media habits.
In this layout, I included the ‘Google RSS Reader’ App, which is also free from the Android Market. With the Google RSS reader, I can add all my favorite news sites to quickly access and retweet. I keep the App icon shortcuts on top to quickly open, check or post tweets – I say tweets because it is synced with the other two social media sites - so each tweet will display also on Facebook and LinkedIn. Below the RSS, I use the Twitter Widget to only display @OnlineMarket mentions so I can quickly respond. Finally, the Google Plus widget fills the bottom space, because, as of now, Google Plus hasn’t provided the ability to grab Tweets automatically yet (vice versa is more likely).
In this layout, instead of using the included widgets, I used Seesmic, a third party Social Media App that can combine you Facebook and Twitter feed. This is good, as you can see on the image, if you want direct access to both feeds and also post your own update. We also used the Facebook & Google+ direct message Apps instead of the main Apps (for those who prefer that).