#3 Google+ (Google+ has replaced Buzz(which was a flop) but it going to be big, you know Google will keep upgrading it)
If you do any pay-per-click advertising (which can be expensive) Bing will give you better quality leads, but Google will give you more leads. Better to have quality then quantity if your paying for it.
Late Breaking News !!!!!!!!
Search and Social........ more conversion!!!!!!
What does this mean? It means what ever you put out in the web can be searched! a status, comment, anything! So be wary of what you say or do on the web. Something people should be doing anyways. Once it's on the web it's out there for ever!
As for business people this is great for SEO!
Here a a couple articles of interest:
I hope you find this interesting and helps you in anyway!