Less than a year ago, Ubuntu Developers announced that Wayland, the new display server is going to be default in Ubuntu, instead of X. At that time it was far too late to get it to Natty, as Wayland needed lots of work, so it was postponed to Oneric. Long time has passed and I haven't heard nothing about Wayland in Ubuntu. Are this plans still considered? Will Ubuntu Oneric use Wayland as the display server? If yes, how will it be done and what will be the consequences? If not, then when can I expect it, and what work around it is being quietly done at the moment?
Answers to your questions are found here: https://wiki.ubuntu.com/Wayland
Long story short, it's not decided when they will switch to Wayland as default, packages are already available for Natty though.