Star Alliance Gold members used to get until October 17, 2013, the same checked baggage benefit (three bags at up to 32 kilos) as United Premier Gold members on domestic flights.
Now United has reduced this benefits just to one bag that should not weight more than 23 kilos.
United Premier Gold members will still get (for now) the benefit of checking in three bags that can weight up to 32 kilos each.
The benefit that United used to give for Star Alliance Gold members was greater than the alliance requirement minimum that is either one extra bag or 20 kilos depending of he weight versus piece concept. You can access United’s baggage calculator here.
I saw a friend’s Facebook update about this change that lead to a thread on FlyerTalk (read more here), where this is now discussed ad nauseam.
United collects billions in ancillary revenue and this is nothing more than keeping collected bag fees going up.
Remember that if your trip starts outside of the United sates the total baggage allowance, including the domestic US flights, is dependent of the operating first carrier or the most significant carrier. Your eticket receipt should show the exact baggage allowance for each of the flight segments.