I just bought it on Amazon (2 day delivery) and I will be able to confirm this on June 8.
I also write blackmagic just now if they tested it or could test it so I had a little peace of mind while I wait even just two days, because I've researched for weeks and this appears to be the only solution.
Yes it does work fine. We use it since a few month now.
Be aware that you will need a powerfull Mac as our MacBookPros (17 inch 2.2Ghz core i7 2011) can only webcast to 350k bitrate and in low res.
It uses more than 3/4 of the CPU to webcast in low res and low bit rates, wit higher bit rates, it starts to show a delay in the preview window and starts dropping frames.
Fast moving objects don't look fluid with higher bit rates.
Webcast Operational Manager
Well, I have my XH A1 Canon video camera hooked up to Shuttle Thundbolt as composite and the thunderbolt to my Macbook Pro (Late 2011 - 2.4GHz, i7, 16GB Ram) and FLM 3.2 does not see my camera.
When I hook my same camera up to my Windows i7, 2.8Ghz, 8GB Ram using my "Hauppauge capture card" as composite it can see my camera.
I'm going to try a simple VHS tape deck and see if my macbook pro can see it using the Shuttle Thunderbolt. I'm going to guess and say it won't.
I installed the drivers as well.