Lenny is confusing "official" and "liscensed" with canon. the first two only meant that the owner of a property (in this case, Star Trek) has authorized someone to sell a book, poster, etc. using the aspects of that property. Doesn't imply or confer any binding effect on the continuity of that property.
Canon, on the other hand, is the collective body of work of that property. In the case of Star Trek this is generally accepted to mean the aired television episodes and movies.
Edit to add: C.E. Evans beat me to it, didn't see his message.