Twitter brought in-line media previews to its mobile apps a few weeks ago; today, it's the Mac's turn. The new Twitter 3.0 app for Mac now shows a quick glimpse of photos from supported services, so you'll know right away whether pictures are worth clicking. A few older features are also making their long-expected debuts, including more detailed tweets (complete with conversations) and full profiles. The new additions aren't likely to give Tweetbot users any regrets, but OS X fans who prefer Twitter's official software will definitely want to swing by the Mac App Store for an upgrade.