Great post crowdedmind, indeed drawing cards without replacement follows a hypergeometric distribution. I didn't follow dormouse's math either but that's not really the point.
Last night working with the math I calculated the probability of beginning (the first 8 cards) of being dealt 1 Judgement and 1 Will provided you have 3 of each in your deck. With a 50 card deck it was 11% and with 55 cards it dropped down to 10%. This 1% is really what all the fuss is over. I see the benefit of a slim deck, but I also can see the benefits those 5 extra cards could provide.
The optimal Magic deck is played at 60 cards and exactly 60 cards because of the sideboard. Without the sideboard who knows what size decks we would see?
... though if it chases away players before they even try to play under this format and learn to grow and adapt to it, it may end up being a Pyrrhic victory. 

*plb plb plb plb plbb* Meep meep! *Pyowwwwwww.......*
