Natsumi Sasada, Japan. WOW. I couldn't decide between this and Daine Dos Santos' front layout mount, but I chose this because Daiane fell off but Natsumi doesn't even wobble. Usually the most daring acrobatic mounts come with a built in wobble.
Incredible strength mount:
We've seen our fair share of one-handed awesomeness on the beam (Mo Huilan 1996 is great) but this in its own category. The sheer strength of that, unbelievable. Jackie Bender gets a good bit of internet kudos for this but is pretty unknown all the same.
Best handstand mount/most interesting handstand variant:
I love how unexpected her drop onto the beam is, it's great. I find the standard press into handstand boring, she shook it up very nicely.
Best show of flexibility:
This mount has plenty of variants- Zmeskal, Miller and others come to mind- bit this is my favourite shaped one! It's no harm either that it's done by the widely acknowledged greatest beam worker ever, Yang Bo.
Best mount sequence:
This just has it all, flexility, handstand, more acro. Beautiful.
These were pretty common, I chose her because it looks so easy and effortless for her.
Most inventive mount:
Once again, Priakhina displays incredible difficulty and another move she didn't get the credit for. (This mount was named for Zamo). I'm a sucker for inventive side-beam mounts and back hip circles. All this AND combined with acro and the splits and it doesn't take too much time..should be used these days.
There are loads more that blow me away, but these are the ones that stick in my head. My absolute favourite is Priakhina's. I'll do one for bars too.