iPhone once OS 4 launches next month. Enter All Things Digital's Kara Swisher, who has a pretty strong track record on all things Redmond. According to her sources, what's being discussed isn't a full swap -- instead, Bing is being considered for an "option" that users can decide between. None of this is what we'd call brand new gossip, and in fact, it sounds exactly like what we heard back in January. So, discussions still seem to be ongoing four months later, which is pretty interesting. For its part, the original TC article has been amended to say the issue is "more complicated" than originally presented. Hey June 7th? You really can't get here fast enough.