Never played with XP but so far (touch wood) win7 hasn't pissed me off yet unlike vista used to do daily
Its very linux-esk if you want to do something that requires admin rights in a normal user account it asks you for an admin password and away you go.
If you want to run a program with admin rights again it asks for the password and it toddles off quiet happy.
The compatability modes run really well as well. None of the cheap games I have tried to run have fallen foul yet.
You can even turn the bitching off which says you system is insecure becuase you haven't tick the auto update box.