If you're still asking why about social media, here's a simple but interesting infographic on Facebook, Twitter and building relationships.
Twitter, Tweetdeck, Hootsuite, Seesmic...all ways to send "tweets" but all have quirks about them.
I've gone from Tweetdeck to Hootsuite and consider it an upgrade. We all start out with Twitter.com but when you become comfortable with Twitter, time to upgrade to something with more options. Hootsuite thus far, appears to be the least restrictive and allows the most number of columns (10) and multiple tabs, each with 10 columns. It's a great way to customize what you want to read by using search terms or hashtags. It's also a simple way to follow any mentions of your name, in addition to Google Alerts. Hootsuite has never crashed on me, is seldom down and allows you to post up to 5 sites simultaneously. Hootsuite uses Ow.ly to shorten URL's and allows tracking. If you upgrade from the free Hootsuite to the $6/month plan, you can post to more sites and can track your stats through Google Analytics which is definitely important to me since I have multiple websites. Save yourself some time by Hootsuite's multiple posting options. Give it a try!