And yet there sat the original version of , with its iPhone-inspired interface and its lack of native retweets, aging unfavorably in light of numerous younger Twitter client upstarts.

That all changed on Thursday with the latest step in Tweetie for Mac’s life, which emerged from its cocoon as Twitter for Mac, available for free via .

When I launched Twitter for Mac for the first time, I knew instantly what the knee-jerk complaints would be. It doesn’t look quite like a Mac app. It looks more than a bit like an iOS app that’s missing the iOS device itself.

Standing there by itself, it looks okay. But on a Mac desktop littered with other windows, there’s definitely something off about it:

There’s no title bar. The Close/Minimize/Resize circles are non-standard and monochromatic. You can drag the window from anywhere on the black bar, but not from the theoretical title bar region.