<...> and the last sketch loaded
this thing is not yet implemented, as far as I understand, even though the "product brief" document says it's possible. They mention it in the Release Notes document in section 1.4: Intel® Galileo Release Notes (1.0.0)
Right now the expected behavior is that if you're booting off the SPI - the sketch is not persistent and disappears during board reboot/power cycle.
If you want sketch persistency, you need to either boot off the SD card (easy, but you need an SD card) or use the solution described in this thread (requires Linux image rebuild and reflashing the board, unfortunately): Re: Can I start a sketch that is stored on a USB drive?