The Singapore CTO was up and running when I was there in mid-October. FWIW, I went in there to change my seat assignment, and it was fairly crowded. I had to wait 20 minutes before I was helped!

It's been said before here, but it's worth repeating: UA uses many factors in deciding whether or not to close CTO's. Obviously, profitabability is the key; it's possible that the SIN CTO sells a lot of full-fare tickets. And you also have to look at long-term leases. For all we know, the SIN CTO could have a 99-year lease! And don't forget the competition--every airline under the sun flies from LHR/LGW to the USA, but how many fly SIN to the USA??? Only UA and NW do as far as the US airlines go...