My brother has a brand new Acer Desktop with Windows 7. I have done many installs (40+) of Ubuntu starting with 8.10, and have never run into this. I've spent three hours trying to do a dual boot install of 10.10.
When you get to the place where you normally would choose to install as a dual boot or overwrite the existing information on the hard drive, that block is just blank. Nothing. No choices even to do a manual partition setup. If you try to go on you get the message "No root file system is defined. Please correct this from the partitioning menu." but there is nothing in the partitioning menu.
I tried a good 10.04 disc also. Same thing happens with it. I ran a gparted live cd, and it shows the hard drive as sda with 3 partitions on the original. sda1 is a small partition called PQService. sda2 is another small partition called System Reserved, and GParted says it is the boot partition. sda3 is the main partation with the operating system (Windows 7) and all of the empty space. There is a little unallocated space at the very beginning and very end of the hard drive.
If I go to places in the Live CD, it shows a 640 gb hard disk called Acer, but it also shows a 640 gb hard disk called system reserved. They are the same disk. There is just one hard drive. If you click properties in the System Reserved 640 gb, it shows all information as unknown. I had to change the boot order in the bios in order to run the live cd. The hard drive instead of being listed as such is listed as Raid:Raid Ready. Something the way this computer is set up is preventing Ubuntu from being able to identify the hard drive partitions at all to do an install, even if you were not doing a dual boot and just wanted to overwrite Windows.
Is this a bug that needs reported? This is a major problem for me and my brother, but also for Ubuntu if new users want to Ubuntu and find they cannot install it.