At a purely mechanical level, as A_Camera says, micro-stepping can give smoother movement. No micro-stepping and a stepper sounds like marbles in a cement mixer. However, because MS uses the balancing of currents between sets of coils in the motor rather than using full current in one coil (full-step positions), the torque available is reduced. In practice, some MS is used and the general recommendation is somewhere around x8-x10, giving 1600-1800 positions per revolution. Note that this is done for smoother movement and does not necessarily give you a corresponding improvement in position accuracy as the MS positions aren't quite as well-defined as full step positions.

There's another factor, though, and that's your motion control system. Say you are aiming at a max stepper speed of 600rpm (that's a bit slow generally but makes the sums easier!) So, 600rpm is 10 revs/sec. Full stepping means you need 180x10=1800 pulses per sec, well within the capabilities of even a parallel-port system. At x8 MS, that becomes 8x180x10pps, 14400pps, which is starting to push things a bit. At a realistic 1000rpm, that's 24Kpps, which is probably beyond a parallel-port system. That's one reason why people use external motion controllers these days - can deliver higher pulse rates to match realistic machine speeds and the more accurate pulse timing also helps smoother motion.