Why?
Well, a few reasons. It depends a lot on how you use Twitter, but I find TweetDeck suits me.
Here are my top 5 reasons for using TweetDeck:
1. It has an autocomplete/lookup function for Twitter names of all the people you are following. No need to guess someone's Twitter handle and have your tweet go off into a black hole because of a mis-spelling (on Twitter, there is no bounce back to tell you that you got the address wrong!). And really, who can be bothered to go and lookup the correct name somewhere else? That's one of the drawbacks of Twitter web (which only shows 500 names - and its never the 500 you want) or Twitter for Mac (which shows absolutely none thank you very much).
2. There is an automatic url shortener which can use your bit.ly account (or tiny.url and a few others). Makes it super easy to copy and paste a url, have it shortened and still be able to access the analytics. If you share a lot of links to content (as I do) then this is important. You can also use your Twitpic, Yfrog or Posterous accounts for uploading images.
3. Its got a built in spell check. Admittedly it is American spelling, but its better than none. Might save your bacon one day.
4. You can use the old and new style retweets - you can choose each time you RT. Love that flexibility - sometimes you want to add a comment onto the RT (if there is sufficient room) and being able to choose how you RT is excellent.
5. TweetDeck shows your RTs. Twitter web doesn't do this very obviously - you need you go to Retweets > Your Tweets, Retweeted to see them - but Tweetdeck will show them in your Mentions column.Extra Tweetdeck Features
There are also a lot of extra features in TweetDeck that you may not be aware of, even if you are a long time TweetDeck user. Here are my favs:
