Macbook battery kaput after 136 cycles

i turned on my Macbook after not using for a few days to see the system restoring from the HD instead of the normal instant awake. Turns out the battery is completely flat and the menu item says Replace Now. This is the replacement battery, the one it replaced had almost 1000 cycles when it stopped working. I'm aware that Li-Ion batteries stop working after a while but this seems so soon.

What is the word on a replacement? Is 136 cycles normal, within the terms of a warranty replacement? Should I bother going to the Apple store? How is proof of purchased handled for batteries? This is just one battery in a fleet of laptops so finding a receipt much less the correct one might be nigh impossible.