This is the about page, yadayadayada, you probably know the routine well enough to dance it in your sleep, but just in case I've got the whole thing mapped out for you here. Keep your hands inside the vehicle, do not feed the fangirls, and all that.
Edmund is one of the most complex characters in The Lion, The Witch, and the Wardrobe, so much so that he has his own in-depth analysis on SparkNotes. Unlike the rest of the Pevensie children, Edmund is not clearly good, and he is taken in by the White Witch, distrusts Aslan, and is genrally quite the bad seed. However, he sees the cruelty and stone garden of the White Witch and eventually comes over to the side of light, being crowned at Cair Paravel like the rest of the Pevensie children. Edmund is known as Edmund the Just, and through his appearances in other adventures, he is a thoroughly reformed boy. (Indeed, it is Susan who eventually falls short of Narnia.)
Of course, Edmund is not my favorite character in the series because he was a traitorous, snotty little child who apparenlty would sell his soul for Turkish Delight. (I really wanted some Turkish Delight of my own, incidentally, after reading the Narnia books, but it turned out to be nasty.) He's my favorite character because he recovered so totally from all that. I've always admired characters who redeem themselves more than characters who are simply good- because it's difficult to be good, and I like it when writers acknowledge that. From a theological point of view, it's also what is ultimately so appealing about Christian doctrine- the idea that even if we have fallen, together with Him, we can pick ourselves up.
You probably already know what a fanlisting is, even if you've never heard of them before, because the name spoils all the surprise. According to TFL, evil overlords of fanlistingdom, a fanlist is "simply an online listing of fans of a subject, such as a TV show, actor, or musician, that is created by an individual and open for fans from around the world to join."
I will call on the mythical powers of Noah Webster for this.
de·lsert (di-'z&rt) noun
Etymology: Middle English deserte, from Old French, from feminine of desert, past participle of deservir to deserve
1 : the quality or fact of deserving reward or punishment
2 : deserved reward or punishment -- usually used in plural (got their just deserts)
This is a weird sort of triple pun (okay, not really) on the word just, which is part of Edmund's title, and the word desert, which is pronounced like dessert, of which a sort is Turkish Delight, and I don't think I need to explain the signifigance any further. When I was younger I always thought it was odd to punish them by only giving them dessert. Seemed like an odd punishment.
Off that weird ramble, the title means giving someone what they deserve, good or bad. I think it suits both sides of moral ambiguity nicely.