I echo most of these sentiments, my trackpad worked fine, but my keyboard began to get finicky, eventually stopped working all together. I tried booting in safemode, creating new user accounts (all using an external keyboard) and even added a special keyboard (hidden within accessibility that will allow for a latched-shift function that allows for special shifted/control/option/command functions that caps lock cannot help with (systempreferences/accessibility/keyboard/enable[checked]). Anyway, I ordered the [product|IF123-130|trackpad cable part from fixit.com] and followed the [guide|45138|trackpad cable replacement guide] (skipping steps 4-16). And now everything works like a champ.