I used TweetDeck as my desktop twitter client. I think it’s too big (i.e. takes up too much screen space), but it’s the most reliable, feature rich client there is, and it’s easy to use.
I used to be able to drag and drop images into the text input box and it would upload them to TwitPic, after the last update it stopped working. It’s taken me some trial and error to work out why, and it’s stupid. If I expand the window so that I can see around 1.8 columns instead of 1, then the text input box says ‘drag links and media here’, however, if I shrink the window so that it’s a more reasonable 1 column wide then it just says ‘drag links here’ and no longer accepts images.
Why the hell does the size of the input box matter?