Many of the more popular Twitter users employ third party tools to help them manage their accounts, but you don’t need thousands of followers to see the value in using Tweetdeck.
The Tweetdeck app is based on Adobe Air and makes use of the Twitter API to pull in the content. It provides a clean and customisable interface that allows you to deal with activity on Twitter in an efficient way.

To start things off there are three columns where you can see tweets posted by your friends, view @replies, and keep an eye on any direct messages that come your way. One of the best Tweetdeck features is the ability to filter tweets by keyword, so you can drill down – instantly – into what your friends are talking about. The immediacy of this function is highly appealing. 
On top of that is the ability to quickly conduct reputation (and other forms of) monitoring on Twitter. There’s no longer a need to set up RSS feeds for a search on Twitter for a keyword, such as ‘Econsultancy’. Instead you simply tell Tweetdeck what keywords you want to keep an eye on. Each search is segmented into a new column within the Tweetdeck interface, and these columns can be moved left or right as you wish.
As you might expect, you can post to Twitter from within the app, which has integrated the excellent URL shortener to make the most of that 140 character limit. 
Other neat features ate the ability to customise the colours of the background and fonts (the default is white text on a black background – I for one prefer a bit more contrast and have reversed that). 
You also have control over how often Tweetdeck makes a call to the Twitter API to look for new content, and there’s the option of turning on a small pop-up that informs you when updates have occurred. It works a little bit like the ‘toaster’ pop-up in Outlook, and might become equally annoying. It can be disabled, if it becomes tiresome.
Additionally you can create ‘Groups’. For example, I have created an ‘Econsultancy’ group, which aggregates tweets by my colleagues (most of them, at least; two are mysteriously missing from the ‘Choose group members’ list). 
All in all, it’s pretty cool and, whether you have 10 or 10,000 followers, is well worth checking out.