I opened Gwibber and added my Facebook and Twitter accounts. The default view has a bunch of icons down the left for accessing different features and message streams, and then a big pane on the right where the messages are displayed. At the top, you can choose from combined streams of messages, mentions, pictures, videos, links, personal messages you have received, and personal messages you have sent. Below that, there is a separate bar for Facebook and for Twitter that let you view those same things, but narrowed to the specific service.
I clicked on Gwibber in the menu bar and decided to see what New Stream would do. All of the icons on the left disappeared, and instead I had two columns of messages with dropdown arrows at the top. I added a couple other new streams, and configured one to be my incoming Twitter feed, one for my Twitter mentions, one for my Facebook feed, and one for my Twitter lists. The problem is that Facebook and Twitter lists columns never populated with any information. I tried messing with the Facebook stream, but could not get it to work.
I don't see anywhere to modify or edit the Twitter lists column in any way, so I can't do anything to figure out why it's blank. But, Gwibber seems to work as advertised for basic Twitter.
I thought I would see what else was out there, so I went back to the Ubuntu Software Center and just typed Twitter. There were five options to choose from: gTwitter, Qwit, Twitux, Gwibber, and Choqok. Gwibber only has a rating of 2.5 stars, but it does have by far the most ratings counted, with 64. Choqok only has three ratings, but it has the highest average, with 4.5 stars.
I installed Choqok and set up my Twitter account again (Choqok doesn't do Facebook). Choqok uses a tabbed interface that has my incoming feed, mentions, direct message inbox, and direct message outbox as options. At the top, though, is a dropdown button labeled More. I clicked it and selected Add User List, and I was able to add a couple new tabs with my filtered lists that I have created in Twitter.
Overall, I like the look and feel of Gwibber better, but it seems flaky and dysfunctional. Choqok seems to work much better. In the end, neither of them is Tweetdeck, though. Thankfully, I can just use Tweetdeck.
Tweetdeck is an Adobe Air application, and Adobe Air is available in the Ubuntu Software Center. So, I installed Adobe Air, then went to the Tweetdeck Website to download the desktop app. Clicking on the Tweetdeck air file installs using Adobe Air by default, so a couple clicks later I had Tweetdeck up and running. Ah, now that's more like it. Forget Gwibber and Choqok.
Interesting side note. Whenever I want to install something or do just about anything, a permission box pops up for me to enter my password to authorize the action. I find it interesting that Ubuntu Linux behaves very similar to Windows 7 UAC prompts in that regard.
One more quick side note. I figure out today that the "Aero Snap" functions of snapping a window to the left or right, or maximizing it by dragging it to the top of the display are part of Ubuntu, and are not unique to the Unity interface.