Not sure if this works in previous versions, but one of my biggest complaints with iCal in Month View was the hoops you had to jump through to set the time given that it was easy to enter a new item (Control-click on date) and set the calender that item belongs to (Control-click the item and set its calender from the pop-up).
When entering an event while the cursor was still blinking in Month View, I accidently discovered hitting that hitting Tab will open the Info window (even if it is detached) and hilight the location field. It would be nice if it hilighted the time field first, but at least hitting tab saves some steps. This will not work if the item is just hilighted in the calendar; it has to be in 'cursor' entry mode -- you can double click on item to get back into this mode.
Now why they simply don't have numbers you can quickly spin to set the time below the to-do window is beyond me.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20040203173809235