Zero. Nada. Zilch.

My wife and I flew on our honeymoon on UA to Bangkok (and TG to other points in Thailand and PG to Cambodia). I used UA miles to upgrade to business. She used US miles to get a business award seat. Worked out mostly fine, except the last leg on the return (SEA-IAD; two-class aircraft which might have worked against us) where UA refused to give her anything but a coach seat (no availability, they said). The big hassle was getting the runaround from United. They kept referring her to US because it was their miles that bought the seat on UA metal.

Weekly phone calls to UA and US for six months did nothing. Appeals to gate agents and RCC agents from DC to Bangkok and everyplace in between did nothing. In the end, I gave up my upgraded seat on the SEA-IAD flight to sit in the back with her.

On the plus side, some UA flight attendants and agents were very nice to us when they discovered we were on our honeymoon. We did NOT try to milk it, because I think that's really tasteless. But even so were given two bottles of champagne (ORD-NRT and NRT-BKK) and some in-flight drink coupons from a very friendly IAD check-in agent. So, yes, there are some friendly folks in the United Skies. Even though miracles can happen and it doesn't hurt to ask, don't expect a bump-up to a better seat.