The reason people don't have backup installed with Win7HP is because of all the OTHER backup programs people install. AKA Norton 360, Live OneCare (now defunct), McAfee, Kaspersky, And the list goes on. HP installs a backup program. So does Dell. And Lenovo/IBM. This exclusion isn't as a differentiator, it's to decrease bloat. It's relevant in a business because they want everything to be 100% QA-friendly, and an integrated Windows backup tool is music to their IT ears, but to a home user, it's just more bloat that they don't need on top of their current solutions.
And for those of you saying "time machine," that's just because apple refuses to let people make a decent backup program for OS X so they had to "do it themselves." All well and good, but with Norton Save and Restore/Ghost, and the volumes of other "backup" programs out there, Microsoft focused on OS and Compatibility and not worthless aesthetic and exclusion.