YES Apple !
This is beyond Ridiculous.
I came from 10.6 around 6 months ago. And ML 10.8.x is one of the most horrible incarnations of your OS in recent memory.
I could customize each individual Alert on my Calendar indepednently from every other one. I did not have to rely on a fixated singular global system model.
I can locally select a different sound from a drop down menu option on the Calendar event in ML and change it to any sound I have showing up in the list.
However - it stays MUTED unless I choose Basso.
Additionally - in 10.6.x I could also customize the START TIME for an ALL DAY EVENT.
I was a little peeved when this began DEFAULTING to 9:00 AM on iOS 6.x (but there was a work-around) -- cannot vouch for Mac Lion 10.7.x as I never used it - but in ML 10.8.x this functionality has carried over.
Why do you think the entire free-world is mandated to start their ALL DAY ALERTS at 9am ? This makes no ****** sense.
Apple is continuously making worse and worse decisions around how their Operating System is functioning. Pushing the Desktop OS to the point that it becomes iOS is not viable.
Blah Blah Blah...Apple doesn't read their forums / discussion pages - BULL. Apple like any other major multi-national corporation filters through every spec of information their customer / users give them.
What's funny is that I am now holding onto a copy of 10.6.x - moving it to a Virtual Machine so that I can bring back functionality like the Calendar items that you have taken away. AND Yes - I can resync these w/ the Calendar in ML and in iOS 6 and 7.
Here's to hoping that some of this has been corrected in Mavericks - but I'm not holding my breath !!
Apple has probably restrained even more customization options in 10.9.x.
@ Radiation Mac -- Jaw444 is correct - this same type of "switch" has been done on many many system elements through the various incarnations of OS X. For some unknown reason - Apple tends to fixate on something like a Background Image or in this case a single System Sound (for everything) and Jaw444's solution is the straight-forward fix. Make a backup of whatever you change -- understand that most audio files are containers for the actual audio codec and that some audio might not work unless nearly formatted identically as Apple does tend to place system restrictions on certain elements - usually for stability. Point is not all MP4s are created equal.