First, I have to apologize for the poor quality of my previous post!
I just fired up a copy of 3.3 so I could compare the calendar to the one in 3.4. It looks like the difference between them is that 3.3 only marks the first day of an event, but 3.4 tries to span multi-day events across the associated days.
The parts that I don't like are the start and end date markers, as they aren't part of the blue strip that marks the days in between. Does anyone feel the same way?