I think he's under some kind of false impression. I've never heard of Vista locking down certain pieces of hardware or checking for piracy not related to itself. Although, I wouldn't put it past MS to implement something like that.
Some possibilities:
Vista originally had a "kill" switch (SP1 removed it) that turned off features and limited log-in time if it wasn't activated within 30 days (3 days after a big hardware change) or if it believed you had a pirated copy. I'm not sure if that's in Windows 7 or not.
There's HDCP DRM which will only allow media protected by the DRM to be played on machines that have HDCP compliant hardware. However, media protected by such DRM wont play on an OS without the DRM implemented either (barring other measures).
The DRM in Windows Vista and 7 hasn't bothered me so far. Registration has been painless and easy and Windows Genuine Advantage (WGA) hasn't made the mistake of calling me a pirate. However, I have never changed major hardware components while running Vista or 7 and have also heard that WGA does make some false positives. One day I might have to deal with Windows DRM issues and that does worry me a bit but not enough to keep me from using it.