So here's my SPIN on things:
We're living in a world where just being online doesn't mean, "I'm available for you this way now." As a matter of fact when I'm chatting with one person, or in a SightSpeed call with someone else, or taking a call which came in over Gizmo, or on my mobile phone, none of the other applications know I'm busy, so the audiences I'm "broadcasting" my availability to haven't any clue what I'm doing unless of course if I change the status on all the tools...NOT. I'm too busy and in a day the number of different things needing my attention, or any knowledge worker is well beyond where it was 10 years ago.
So what Alec is proposing is a clean up of the imperfect, immature and still evolving world of being presence in the context of being "public" without being "open" all the time when it comes to planned and unplanned real time communications.
To me iotum's Relevance Engine is a needed solution in the game of attention management, something that is rapidly being over run by the attention deficit like behavior by so many in the business world. My spin on this is that iotum is the prescription for a ailment that is just getting recognized. Think of it as the Viagra for the overworked, over emailed, over phone called, over IM'd types of people who are coming on line more and more. With iotum, you can be up, and present, when you need to be, not turtling when the hot opportunity opens up.