There seem to be a few threads on this issue (some focused on the outline plugin) and some not. I thought I would add an additional entry since I still see this problem with the latest release (7.00.1). At some point during the version 7 beta process this problem went away… and then it resurfaced. What I have found is that when the outline plugin is not active, only the current line is affected (e.g. the text flickers when typing quickly). When the outline is enabled, other lines are affected. The easiest way to reproduce is to open a text file, type as fast as possible (e.g. aldskfja;dlkfjad;lkjdsa;lk) or hold down the delete key. It’s much more prevalent when the outline plugin is enabled.
I don’t think it’s a hardware problem. I have seen this on multiple machines. Laptops, yes, but new Thinkpads (t60, t61) with fast processors and discreet, higher-end graphics.
Please let me know if there is any information I can provide to help troubleshoot.