Why is this component that looks like a capacitor with ground lines in this circuit diagram different from a polarized capacitor?
It's an electrolytic capacitor, but they used two different symbols for electrolytic capacitors (10\$\mu\$ and 2.2\$\mu\$) for some reason. Perhaps one or the other was added at a later date. 

Note that the datasheet also (in print) recommends 10\$\mu\$F connected to pin 13.