After playing with the OS for about 12 hours now altogether, I'm going to assume Lion will come in at the same price as Snow Leopard. There is nothing there to compel people to do an expensive upgrade. Launchpad is the worst. Apple seem to be touting this as the main feature, but it is nothing except a glorified Finder view with pretty graphics. Mission Control has potential, but right now is cumbersome and awkward. Full Screen implementation right now is also awkward, although it is evidently a work in progress. I do like the new Mail client, and I do very much like the new About This Mac. I also like that Resume can be disabled through the CTRL+Eject shutdown shortcut.
For any expecting big obvious changes, I think you'll be disappointed. Yes, there are changes here, particularly in Finder, but will they be useful? Probably not. I'll hold out on judging Mission Control, as it's clearly not finished, but I won't give Launchpad that much leeway. It's just useless.