As I'm shopping around for flights these days, rather than defaulting to BA, this is one thing that I actually miss.

I book a lot of travel at short notice (almost all under 3 weeks, some much shorter than that). I've just booked a flight to the US next week on UA, and there are no decent seats left. As a GCH I've been spoiled because I can usually bag a good seat in whichever class, at short notice thanks to their seating policy.