As the ZDnet article already mulls, this brings up a few questions about just how different Windows 7 is going to be from Windows Vista. Microsoft's Steve Zinofsky has already explained that Windows 7 will not make any major changes in kernelland and the driver models, but that it will include a number of major features (of which the multitouch framework is about the only one we know).
It's not uncommon for Microsoft to release major versions of Windows that internally are pretty much alike. Windows 2000, Windows XP, and Windows Server 2003 are very alike underneath, to the point that drivers are cross-compatible. For instance, if you are looking for nVIDIA drivers for your videocard, you need to pick the Windows XP version if you are running Windows Server 2003.
In any case, Microsoft will shed more light on Windows 7 later this year during its Professional Developers Conference in Los Angeles.