I actually read this on mommyof3 blog. (Great blog by the way, your kids are too adorable.)
In her list of why someone would think her children were spoiled, nursing her daughter past 1 was on there. I have heard this from my mother and occasionally from my husband, that letting my daughter continue to nurse (she just turned 2 on Sunday) was spoiling her.
I say if letting her get all the extra calories she wouldn't be getting on those picky toddler days or letting her continue to have a great immune system (she is 2 and has had 1 major cold. We have never had to give her antibiotics.) is spoiling, then I'm going to spoil her rotten.
However, like momof3 said, spoiled is a horrible word to use in regards to children. Working in the NICU at Children's I had a nurse tell me how you could tell if a child was getting spoiled. You look behind their little ear and check for mold.