The N80 is available now with Orange for new customers at £49.99 (
www.orange.co.uk)
It isn't unfortunately available as an upgrade yet. According to some Orange employees, it should be available as an upgrade in the next few days. How accurate that statement actually is, is anybodys guess.
I'm thinking about upgrading to the N80 myself. I have a SE W800i at the moment, but I feel like a change.