Ive been through the posts on these feature request and hope I am not just repeating what has already been requested but.
I was working with my partner (he has xsi) and have always been jealous of the fact that he can draw a limited region around an object or scene in one of his viewports and have it interactively render as he makes texture adjustments, What makes this special though is that with it still active he can rotate,resize,move to see all sides of the object and get realtime feedback in the region.. AWESOME... is it possible to do this in a future version of LW.

Dont get me wrong. Viper is great but a feature like this would be a spectacular upgrade. BTW (all else aside) LW Rulez!!