I've never played Black and White, but as a writer I understand the appeal. I spend my days creating fantasy worlds where imaginary people live in imaginary houses and do imaginary jobs. I can see my world clearly in my head, but I've never been one for making notes or drawing pictures of my world - I think the only time was in A Single to Rome where I drew out a complete floor plan of the Tea Museum to make sure that it was consistent throughout. For other writers the creation of a world is one of the joys of writing. If that's you, then be careful. It's all too easy to get caught up in the minutiae of your world, to the detriment of your writing.
There are two problems: firstly, you spend so much time developing your world you forget about writing the story, and secondly you can't resist sticking all your lovely ideas and plans into the story. It's a particular problem for fantasy and sci-fi writers where the creation of a whole new world is very much part of the genre. Think of Lord of the Rings. Tolkein had the sense to put all the elven lore he'd developed into another book, The Silmirillion. JK Rowling is another world builder, and equally put a lot of the more obscure elements of her carefully detailed world into books like The Tales of Beedle the Bard and Quidditch through the Ages.
Not everybody manages to separate the story from the world creation. My heart used to sink when I was teaching undergraduates and yet another slice of fantasy world came up, crammed with detail about the rituals of the Gar'an or the native folklore of the 'Mqardl that only the creator could love.
It's not just fantasy writers though. It applies to anyone who needs to research the background of their novel. Kissing Mr Wrong has a WWI background which led me to spend time on the Somme battlefields prompting the comment, 'Too many cemeteries' from my editor. Oh, how I hated cutting back on the cemeteries, but she was right to be ruthless. I'd written about too many because I'd been overwhelmed by the places myself, but they didn't add to the story. Instead I've put the information up on my website. It's the best place for it.