Earning Points. Starwood's Preferred Guest program is fairly straightforward: the more nights you spend at participating hotels, the faster you'll earn a free night.
As seen in the EXECUTING phase, the map will write (using Mapper.Context.write()) its output into a circular in-memory buffer (MapTask.MapOutputBuffer). The size of this buffer is fixed and determined by the configuration parameter mapreduce.task.io.sort.mb (default: 100MB).
No. LILO stores information about the location of its own map file in the MBR; GRUB can optionally do this too, and the only way it can avoid it is the horribly fragile stick-stage-1.5-in-unallocated-sectors kludge. Unlike LILO, GRUB has a web site.