2010/4/3 Naoko Komura nkomura@wikimedia.org:
When the default interface is switched, the tab navigation on top, the left navigation, and the toolbar will be changed mainly. Forms such as upload forms will not be affected. I see what you mean by how the tab navigation is not lined up properly if your language preference is in RTL. The user experience tech team is looking into how we can improve it.
Addressing this problem properly is tricky and will take some time (I personally think it's a task our team should take on after the Stanton grant expires), but it shouldn't be very difficult to come up with a quick JS hack that reverses the tab order. I should repeat this is not an issue specific to Vector: when viewing Commons in Monobook with an RTL user language, you're basically seeing an LTR interface with a pile of hacks on top of it to make it look like RTL. It's just that these hacks are less complete for Vector, and also more difficult because of certain layout differences between Monobook and Vector.
Roan Kattouw (Catrope)