I received my iPad Pro 10.5 Smart Keyboard this evening, and I attached and compared it to my 9.7in iPad Pro. It looks like there is a 1-2cm difference on all sides.The spine is also about 2-3 cm longer on both sides.
		
		
	
	
		 
	
		 
	 
This photo is the iPad Smart Cover 9.7 in directly on top of the 10.5in iPad Pro Smart Keyboard. You can see a similar size difference.
The 9.7 in accessories won't work with the 10.5 in. And it looks like the 10.5 is very close but a bit bigger than the 9.7 in.
		 
	
	
		
			
		
		
	
				
			 
	 
	This photo is the iPad Smart Cover 9.7 in directly on top of the 10.5in iPad Pro Smart Keyboard. You can see a similar size difference.
The 9.7 in accessories won't work with the 10.5 in. And it looks like the 10.5 is very close but a bit bigger than the 9.7 in.
 
	