Dont worry man. They will not be snowed in. It stopped a few hours ago and clean-up in already well on its way at the airport. The indicator probably needs to be updated. They usually have around 25 applicants each month, there have been cases where they took fewer but that month they also had more than one interview (June 09 and July 09). If they invited you, they have a spot for you. On paper you are capable, but you just have to show them that in person. Don't sweat the # of applicants. When I was there, besides our 25 there were NROTC guys, USNA guys and Prior guys so the conference room is quite packed.
"Tougher" and "Easier" is arbitrary and completely depended on you. If you struggle, then you are screwed and if not it will be the happiest day in your life, IMO.
The Admiral can/will take as long as he likes to make sure that you deserve to be in his elite program. The more time you spend in his office, i take it as the opportunity to convince him that you will do well in his program. If you feel you did well in the technical interviews and are in the Admiral's office less than a minute, it "usually" is a good sign.
I will tell you this, do not worry about how many people are there and who does what. It does not matter at this point, be glad that you have the invite and kick ass at the interviews. It does not make a difference if they invited only you or the entire state of Oregan, if you do well you will be fine. No need to put the extra pressure on yourself by thinking about the variables you can not control. Good luck and post your experience on the 11th. We want you in our Nuke family!!!
Cheers,
Seawolf