1. The book would be called Windows to the Goddess.
2. Iconology was be a major chapter.
3. A revised edition would be released approximately every 6 months without which your magic would no longer work.
4. Your broom would crash at least once a week.
5. Cauldrons would be called recycle bins.
6. A book of shadows would be called the folder of magic.
7. A free high speed connection spell would come with every book.
8. Ever now and then, your circle would collapse and you would have to perform the reboot ritual to get it working.
9. If you used the more powerful MagicNT rituals, the above would happen to all circles within a 5 mile radius.
10. At least once a month, you would have to reinstall your spells into your folder of magic.
11. You would have to use a start ritual to exit your circle. (And cake and wine would only be available after a sign from the Goddess saying it was safe to do so.)
12. The spells would be called simply “Banish,” “Purify,” “Dedicate,” etc., and these names would be trademarked so that no one else could use them.
13. Everyone would use the spells in the book, because everyone would have it laying around and could assume others knew it too. In an unfamiliar group, you could be sure that everyone knows “Banish,” so it would be convenient, and you would get used to it.
14. It would be illegal to let other people cast the spells in your book or vice versa. (Of course, everyone would do it anyway.)
15. The book would be outrageously expensive. Other, cheaper books would exist, and also free ones on the internet, but it would be harder to use them because you wouldn’t be familiar with them and you’d have to get used to a whole different metaphor. Most people would think it perfectly reasonable to use Bill Gates’ book and pay his fees.
16. If you had questions about the spells in the book, you’d have to call in to an enormous tech support system and pay for “incidents.” (Or get your 9 year old niece to show you what to do.)
17. Due to agreements with altar manufacturers, the book would be packaged with every altar sold, and you would have to pay for a new book when buying a new altar. Furthermore, no one would be allowed to use the book they already bought with a new altar, only with the altar the book was purchased with. To use the book with a new altar, it would be necessary to buy a new copy of the book for the new altar, and throw the old copy away (like OEM operating systems).
(Author unknown; various versions exist. I found this one via Butterflies in my Stomach.)