The task toggle on RTM shows up scrollbars (apparently text size has nothing to do with this bug) and causes scrollbars in place of text. In Compose/Email, the same effect occurs when entering text input in the TO: section. This requires reducing font size under 12px, which is way too small for me to view.
Your design updates are fantastic and I am actually encouraged to use my gmail web interface over thunderbird. Good job, Ev!
About Gmail Redesigned (by Globex Designs) on Apr 07 2008