Actually, I never did notice this before, so I just had to check it out after reading this

Guess what! KOBO DOES HAVE THAT EFFECT! The backside of the pages when you flip a page DO have that effect! You can see the backwards text from the previous page kinda shining through! You can notice it a lot more if you drag your finger slowly and hold the page curl so the page is half way flipped... you can easily see the effect you were talking about.
So Kobo seems to be the most similar to iBooks for looks and functionality. I do miss however, the sepia effect and the nice red bookmark on iBooks... Kobo uses an icky green! I also miss the nice wooden bookshelf. Kobo has a white metallic looking one. Just small differences. I do like the Facebook integration with Kobo though!