I have made both iPhone and Aperture books. Since Aperture was updated to 2.1.2 I have heard that the quality is through the roof. iPhoto on the other hand is still the crappy quality it always was.
I say make your books in Aperture (version 2.1.2) to get the best results.
If you want the the books for Christmas you need to get them off ASAP. I have found that the books take at least 3 weeks to be delivered as they come from the U.S.A. Your books might get caught up in the Christmas holidays and not be delivered on time.
iPhoto book quality was 5/10
Aperture book quality was 5/10 (same as iPhoto)
I haven't tried a new Aperture book yet, but I've heard they are very good. The books I printed last year are O.K, but I wouldn't call them very good. They are alright for mum and grandma to pass around, but they are not what you would call professional quality. Since 2.1.2 though this issue should be sorted out.