So far I have been waging this war through my iPhone. However, I have recently started using the PC version of one of my iPhone tools, and like god on Tuesday night, I like what I'm seeing.
My iPhone Twitter experience had me going through several apps, looking for a proper partner. I started with Echofon, moved to Twitterfic and even sampled Twitter's own app (pretty bad); all were less than satisfying in too many respects. Following a friend's recommendation I tried TweetDeck, and from then on, as they say, I haven't looked back.
TweetDeck can be installed on your PC as well as your smartphone. On the PC side of things it can cater for more than Twitter: it allows you to link your Facebook and LinkedIn accounts too, as well as many other forms of social internetting activities. You can filter, list, and do a whole lot of things and it just works great. In particular I like TweetDeck's ability to filter out messages, allowing me to get rid of all those stupid Farmville updates that seem to dominate my friends' Facebook activities.
Most of all, I like TweetDeck's user interface.
Is it flawless? No. TweetDeck's biggest problem is that it's a third party application, so in effect you're letting a third party access your privates, passwords and all. When it comes to Twitter and Facebook I'm fine with that; I have no state secrets there. Do consider security and privacy before taking the plunge, though.
I have installed TweetDeck on my Linux PCs. It's available for Apple and Microsoft suckers, too.