I just upgraded ~30 minutes ago, still at 98%. It's a good sign, but I was worried when there was nothing about it in the notes. Will report back when it's closer to 50% or so (I've been getting ~4-5hrs after a typical 8-9).
Edit: So far with half brightness and daily apps open (Mail, Safari, iTunes, Terminal > vim, TextMate) OS estimates 7:39. It feels like it's still going a little quick, but I could be wrong as I don't always leave iTunes or Safari to do their business.
Mid-day followup: original post at 1pm, had been running for ~30m.
Current time... 4:05... close TextMate, open InDesign. 56%, est. 2:22 remaining (obv. due to InDesign, even with a small file). No change in brightness.