I think they are underestimating the time it will take. AOC's leveling time seems to me very similar to EQ2, I bet they will find the average player (who does not spend every minute online levelling) will take quite a bit longer. Given that I play about 2.5 hours a night I find it unlikely that I could get to max level in 100 days, that's just a little over 3 months. I have a feeling it will take 1.5 or 2x their estimate.
Edit - weird this was a reply to the thread on how it will take 250 hours to get to max level. Somehow it got put in it's own thread.