So I saw the Corsair RGB today. Due out in September, this is Corsair's rival to Ducky, both in terms of backlight configuration, and price.
Here is the K90 in action (sorry for crappy video quality gif)
EDIT - Gif is still ****ed. Coming soonTM
My first impressions were that the colours are washed out. Nowhere near the intensity of the Ducky, V60, or even Razer backlight. After removing a switch, this was what I found.
More
(http://i.imgur.com/Ox5m923.jpg)
Clear switch housings that are being uniquely distributed to Corsair by Cherry until the end of the year until they are released to other companies/parties. This could be an explanation as to why the colour isn't as intense as the others. The LED is deep inside, but it does mean that, due to Corsair's design with the switches mounted on top of an aluminium case, the light is very spread out across the board and does look quite good.
I wasn't allowed to take photos of the software that one of the Corsair guys showed me, as the machine was using the old testing software that was without glitches, as opposed to the new beta software he said was a bit temperamental right now. On the face of it, it is very user friendly. You can drag over groups of keys to change their colours, or change individual keys etc. You can use a colour blend thing (not sure of the technical term) to pick absolutely any colour (out of 16m) to apply to the back of your keys.
The software then got a bit more complicated, where you could add animation layers to sections of the board, with different colour change patterns, such as pulsing activated by key presses or just automatic, breathing effects, waves as seen above, and much more. I've never had a backlit board with such capabilities so I wouldn't know how this software differs from other board in it's field.
As for the build quality, I thought it would weigh a ton, as my friend's old K70 does, but infact it's lighter than my KC108, surprisingly light for a fullsize board with 18 macro keys.
Price wise - In the UK the K90 will retail at 170GBP. The K70 at 140GBP. So right in ducky's window.
More pictures can be found here
More
(http://i.imgur.com/OP3KtVq.jpg)
(http://i.imgur.com/qELysif.jpg)
K70 in German ISO layout
(http://i.imgur.com/0VzVkBB.jpg)
(http://i.imgur.com/DWoLR9E.jpg)
(http://i.imgur.com/J3l5PJP.jpg)
(http://i.imgur.com/MI4G8Q1.jpg)
(http://i.imgur.com/Ox5m923.jpg)