Assuming this isn't a just a rumor, this reeks of corporate politics. Loren creates an app that gets peoples' attention. Loren leaves. Twitter for Mac slowly dies. I don't doubt that someone has a rationalization for this, but I have to question the motivations behind such a move. This sounds more like someone trying to get rid of someone else's "legacy", or at a minimum some "new guard" trying to get rid of the "old guard". The Twitter Mac App is well-designed and popular. What good reason could twitter have for killing this?

It sounds like twitter's attempts to "reinvent" itself are going to just push them further into irrelevance.

Of course, if this is just a rumor, then you can pretty much ignore the entirety of my rant.