Just to throw another irrelevance in, I have a core which connects then will blink blue after 6 to 30 hours. The core has never been programmed and is not physically connected to anything. New out of the box and set up with the Android app.
I understand interrupts will increase the likelihood of the Blue Blink of Death, but there is obviously a fundamental issue. I sure the SparkCore folks will nail this. Just my $0.022 (at current exchange rates).