The trackpad board contains several connectors and two prominent ICs:

Silicon Storage Technology SST25VF020 2 Mbit SPI Serial Flash

Up until now, we haven't noticed the inclusion of flash memory on the trackpad. We don't know why a trackpad would require flash memory. However it seems that it was also included in the MacBook Pro 15" Retina display trackpad.

Broadcom BCM5976 touchscreen controller (as found in the iPhone 5.)

What a funky looking trackpad set screw. This standoff screw is much bigger than those found in previous generations, and is held in with threadlocker.