Now that would be cheating! If you look carefully, you can make out the position of the tiny dots that stick out from behind the 'blank' ( I have good eyes :p ) its not difficult to work out which letter it is.
( you're going to be staring at your screen now - magic eye memories!)
It's weekly, Jubieanna, but with a few extra quizzes thrown in, such as this one (which I linked to, in another post, earlier this week):
http://www.bbc.co.uk/news/magazine-12974903
(The '7 Days' links, from that page, will also take you to the most recent weekly quizzes)