Hmmm... 3D TV and Sky TV, and now I see how some of it works.
First off, yes, the 3D effect works - there is depth. That is the plus point... I seem to be able to watch live football in 3D! (I don't watch football).
Now for the crap...
1. It appears that there is no signal to tell the TV that the feed is 3D - you have to turn on and off 3D mode on the TV. It is thankfully one button. And to be fair you have to put glasses on, so that is not so hard. I think this is a limitation in the Sky box not telling the TV it is 3D to be honest.
2. It appears that a 3D feed is just a squashed picture and another picture on the same frame. I.e. it is not actually two full HD pictures, but two half resolution pictures. Con or what?
3. It appears there is clearly no standard for that, as the TV has top/bottom or side-by-side modes. Sky seem to send side-by-side. So if you watch Sky 3D on a normal TV it is just two images width squashed, side by side on the screen. Seems you can get 3D for free too, so you can try that on a normal TV for a laugh. Arrg! The TV forgets the setting...
4. The TV, a nice (expensive) 55" Sony, is fine I am sure, but I can see the flicker with the active glasses. I expected that this might happen. I have yet to see if I can get used to that. We'll see.
5. This crazy way of sending two pictures for the price of one does have the side effect that existing kit will just work as it is not aware it is doing 3D, just a rather odd picture. So it will just work with a blue ray player, or whatever, that has 3D.
6. The sky box has no clue it is 3D (see above), which means the menus, and the pause logo, and so on, are all seriously screwed up. The sky box needs to know, and to display its menus half width on both sides. I am sure that would be easy for them to do, but they have not done it. Doh!
So, not entirely impressed yet, and shocked that 3D seems to be technically a bodge on normal HDMI.