You are of course correct Mixture. However, it remains the case that downloads of Windows 7 builds are a useful method for MS to gain feedback on the progress of the os and thus MS are happy to look the other way. I'm not going to argue the legal position, rather the realpolitik that the geeky community experience every time MS need their products testing widely.
Edit to add, each iteration of 7 thus far is time bombed. 7068 hih has been the latest for example expires in July. This clarifies what MS expect of this software to me. Now if you were to break that expiration, that would be very naughty indeed....