in addition to FlyBoy's:
ability to e-ticket more than 4 segments (why not 16?) on one ticket (revenue or award)
ability to book more than 8 segments (current limit in Personal Ticket Office) on one ticket (paper or electronic, revenue or award)
re-emphasize booking by fare class by segment -- remember we do not mean general fare class, we mean exact fare code like VX1NYR etc.