Installer does not inform user that it can setup a dual boot system with operating systems like Windows

Triaged to Confirmed. Yes, there should be something to that effect. There should also be adequate warnings since new users do all sorts of creative things to destroy their Windows partition.

Triaged to Confirmed for reasons stated in Ubuntu ubiquity.

I'm not convinced this belongs in the installer. Wouldn't this be better in some supplementary documentation, like the CD sleeve for pressed CDs, or the download page?

I agree Colin, that it should be printed on sleeves and any included supplementary documentation. How many times have you gotten a copy of Ubuntu from someone else that burned it? (No printed sleeve.) Viral nature of Ubuntu installs would dictate some type of pop-up dialog during installation or bring up a document (invoked when installer is first loaded). It doesn't need to be click-through (like a EULA) but it should be prominent that there is some risk if Ubuntu is installed over and not next to an existing Windows partition. Having spent the past two years answering posts on the forums, there are several cases of users destroying Windows (on their Dad's machine, no less).

Anything done to reduce destroying Windows partitions will help because as Ubuntu user base grows, so do support requests.

Whatever warnings that are given, they should not interfere with automated installation, nor take any more time to perform the installation.

Fixed in Natty.