In two builds now I've seen that Windows 7 creates a small partition of 200 MB or 500 MB to house the system files, bootmgr and the folder Boot. Even if one selects Disk 0 Partition 1 to install on, the small partition is first created before installation starts. Here's a screenshot from Windows 7 and another from Windows XP on the same system. Interesting that Windows XP placed it's boot system files (ntldr, NTDETECT.COM and boot.ini) in the little partition too.
I still need to figure what the implications are for dual booting, but it wasn't too much of mission to get XP installed and a dual boot functional with Windows 7 installed first. Oh yeah, there was no drive letter allocated to the small partition, so I allocated the first offered, thinking that would be necessary for XP to be able recognize it.
Disk 0 and Disk 1 as per the XP screenshot, were added to the system after installing Windows 7, so at the time of installation Windows 7 was installed on what showed up as Disk 0.
"The great majority of mankind are satisfied with appearances, as though they were realities, and are often more influenced by the things that seem than by those that are." - Niccolo Machiavelli