My various stays at the GH Beijing (all at the same corporate rates) yielded wildly varying results--2 no-upgrades, 2 RC upgrades, and 1 suite upgrade. In each case, the hotel was not close to a sell-out situation.
I think the lack of consistency is one of the most frustrating aspects about this hotel--whether in terms of the front-desk response, concierge recommendations, the (in)ability to trust the bell desk for reliable, reasonable transport. I don't think I'm exaggerating in suggesting that when in China, prop up your "buyers beware" antenna.
One alternative hotel that I'll definitely visit again is the Peninsula Beijing. It's very centrally located--around the corner from the GH, charges similar rates as the GH, and has much larger and more luxurious rooms (32" plasma screen TV in the bedroom and 14" swivel LCD TVs embedded in the marble wall of the bathroom). Service quality, however, isn't any more consistent than the GH.