An OS installer that almost never fails, and only fails gracefully.

Previous install CDs for Ubuntu seem to fail very frequently (> 50%), regardless of the media or system. When they fail, the user is often left with a partially-installed but unusable system and a new bootloader that doesn't see any other partitions; the system becomes unusable, as it can no longer be booted into the other partition (assuming it exists) without recovery work. OS X and Windows installs, on the other hand, almost never seem to fail. The Hardy installer should do everything possible to provide the user with a bootable system; missing software should automatically be downloaded and installed later via Ubuntu's repositories rather than causing the install to abort. The installer itself should try downloading from repositories. The installer should copy the user's configuration to RAM while initializing. If it hits some completely unrecoverable error and the user has opted to keep the original OS's partition (resizing, etc.), it should offer to restore the configuration so the user at least has a bootable system.

Install errors may currently be recoverable for techies, but certainly not for less technically-inclined users. Install should be rock-solid and not leave users with a broken system that they may not have the skills to fix.