Thy art lucky lad*.
We'd dream of be able to only have to go back as far as IE7.
We still have client's on IE6 and that have no migration strategy.
We also have a bunch of clients who are getting ready to roll out their upgrade from Win XP to Windows 7.
IE7, ha. Lucky bugger.
* The author of this post was born in Yorkshire and knows the the Four Yorkshire Men sketch pre dates Monty Python's Flying Circus.