Here's some vmstat output I just got:

   1  procs                      memory      swap          io     system         cpu
   2   r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy id wa
   3   2  5 375912  19548  17556 477472    0    1     0     0    1     1  1  0  0  1
   4   0  4 375912  18700  17556 478264    0    0  1044     0  774  1329  8  1  0 91
   5   0  5 375912  17664  17556 479168    0    0  1160     0  764  1110  8  1  0 91
   6   1  8 375912  15836  17568 479796    0    0  1144   840  751  1622 16  7  0 78
   7   0  7 375912  19340  17576 480224    0    0  1224   148  587  1958 17 18  0 65
   8   2  0 375912  18288  17588 481036    0    0   812     0  845  1732 18  3 21 59
   9   0  2 375912  15868  17588 481528    0    0  1012     0  588   941  4  1  5 90 

r - processes waiting to run but that are held up by the CPU
b - processes sleeping (usually waiting for IO)
swpd - total swap used (in KB)
free - total free memory
buff - total buffer memory
cache - total disk cache memory usage
si - memory swapped in from disk (in KB/sec)
so - memory swapped out to disk (in KB/sec)
bi - blocks read in from IO devices (blocks per sec)
bo - blocks written to IO devices (blocks per sec)
in - interrupts per second
cs - context switches per second
us - userland CPU usage in %
sy - kernelspace CPU usage in %
id - CPU idle %
wa - CPU IO wait %