@spivonious: I think Alphabet is now the holding company of Google. Since the instrument code for trading market is not changed (still GOOG), this means most likely for the government record it's just a name change for company, and they start up another company named Google for holding what Google currently actually does.
One thing I can think of is that, Google has grown into size as Microsoft and has been subjected to same sort of antitrust lawsuit. After the reorganization, if Court say Google has to split to satisfy them, the impact to the company would be trivial.
The company split also mean more challenge to their talent management capabilities. However since they're experts to data managment I think there would not be much to worry about. Btw, because of this I suspect by 50% chance Google will release some kind of HR related tools as byproduct of this action.