I got Denim on my 930 like a day and a half ago.... Before that I kind of just given up on Denim and figured I'd get W10 before Denim was available. Now that I have Denim, W10 is the next logical choice for me.
So far my battery lasts longer, the Hey Cortana thing is helpful in a few situations, the camera apps are snappy and the 4K video thing sounds pretty nice, though I have yet to record a video since I updated.
But I am still looking forward to W10, so long as I don't lose any of the features I just gained in the last year. If so, then I will probably wait until things are about par with what I have now.
However, if W10 adds features right off the bat that I am interested in at the expense of a few features I don't use all that often, I may update to it right away.
Now if only my 930 can get Glance, I'd have the full package.... Just slap on the new W10 UI and those universal apps and I'll be happy.
.... Oh and the ability to rotate the Start Screen to landscape... Icing on the cake.