Facebook for sure. I know among my group of peeps, twitter is looked at negatively. Facebook is still on top.
I feel Facebook is more spammy since anyone can post in your wall tons of irrelevant junk unless you make some features private, hence what you need Facebook for if users can't see it that way? I know Twitter has tons of junk too, but limited to 140 characters, not tons of useless text, photos, vids or annonying apps.
Facebook and Twitter both have their strong points, but I personally prefer Facebook because on Facebook you can view not only posts and photos but also videos. Twitter, however, has another program which is useful if you do plan to use Twitter. This program is called twitterlocal. Through twitterlocal, you can narrow down your searches if you are trying to target a specific demographic for work by typing in the specific city where you would like to reach out to people. By typing in this city, twitterlocal will show you all the tweets by people in that area, and then you can proceed to sign onto your twitter account and add those people.
I see facebook as a little more intimate than twitter. It has many more functions and you can use it to build relationships better than twitter. You can update your status in a way thats much like twitter, photos, videos, the possibilities are endless with facebook, they also have many applications you can utilize as well. One of my favorites is the html apps in which you could use as a way to help with list building by inserting your aweber or getresponse opt in butttons. Works very well once you provide useful information and build relationships with your friends.
Personally, I prefer Facebook. And if we are talking workwise (I manage a few pages/groups etc. that are work related community and/or marketing pages) I would have to say facebook as well. We use Twitter aswell, but thats basically to market facebook and our website. I found out that our local newspaper offers a twitter-feed on their website, so Im using the work-related Twitterprofile to generate traffic to our facebook and website
I would say use both....can't hurt. And Twitter doesn't take much time. Be careful, FB is a time devourer.
I've used both and I prefer Facebook, there are a lot more things that you can do with facebook and to make it more appealing to people
Facebook rules over Twitter, it has everything you can ask for in a Social Networking site. Twitter, on the other hand, doesn't have a lot of great features.