We are on 2010.3.1326.1040, the problem described by original sender still exists. We have the same business case as the sender.
The keyboard support for date picker is excellent I am just wondering when Time Picker will be treated same.
The issue can be observed on the demo site.
When input mode is TimePicker, the clock opens, when you repeatedly click on down arrow, you will notice the selected date changes a day at a time but there is no selection or Time picker movement in the clock. Since the Calendar is not visible and the fact arrow key actually changes the value of the selected date, i believe this is a bug too.