When dragging time block limits in week view, it would be great to have the bar snap to a preset time interval, adjustable at either a global or project level.
In 1.0 you can snap an entry to 15 minute increments by holding down the shift key while dragging.
In 1.5. auto-snapping can be turned on in the preferences panel so that no key needs to be pressed to snap. Also, the time increment, in minutes, can be set on that screen.