Charlotte Blakey 29 May 2014 from http://ipcopy.wordpress.com/2014/05/29/black-and-white-trade-marks-change-in-ohimipo-practice/
writes the following:
Previously, it was common practice to file for a trade mark in black and white, or grey scale, in order to obtain the broadest protection possible. It was accepted that a mark registered in black and white would allow the proprietor to use the mark in colour and maintain protection. Essentially, it allowed for one application to be filed in black and white, instead of numerous applications for various colour combinations.
However, the recent decisions indicate that a black and white trade mark will only provide protection to colour marks where the colour change is so insignificant that it would not be perceived by the average customer. Examples of such insignificant differences are below:
1)
2)
3)
The following marks, however, would be considered as significant differences and therefore would not be considered identical. This means that the black and white image would not protect use of the mark in colour.
1) 
2)
3) 
With the above in mind, we can no longer advise clients that a black and white mark will cover all colour variations. Instead, this will need to be assessed on a case by case basis.
It may be the case that a black and white version is filed at the outset, but that potential colour variations should be considered and filed at the same time or at a later date. This also means that clients will need to consider how the mark will be used at the time of filing and in the near future to ensure that they are fully protected.
Additionally, clients who have registered black and white trade marks, in line with the previous practice, will now need to think about filing new applications for their marks in colour, as well as any colour variations they may consider using in the future.
Trademark24 