I can confirm now... for anyone that might have the same issue.The black bar is indeed a defect. I returned the Nokia 770 and got another one (fromadifferent store) which doesn't have the display artifact. So if anyone has this problem, definatly go return it.

Yup, it's an effect of a multi-source backlight (on the right anyway). This was one of the first oddities pointed out here and so far as we could all tell, it's stock-standard in all units. I don't find it too bad unless I'm reading an eBook (ie white background) in the usual lighting. Even so, it doesn't bother me too much.

Hedge,
I meant the black bar on the left, not right. I still have the "stage lights" on the right. It is the solid light grey bar on the left that is an actual defect, not an "acceptable defect". :o