Ok, I'm going to give this a try.
Basically, the premise is that within 6 weeks you can go from being able to do as little as 15-20 press-ups (although it does say less) to doing 100, by following the training regime here:
http://hundredpushups.com/index.html
I've not done the initial test yet but I reckon I'll do about 20 - somewhat short of what I used to be able to do, but I am 30% heavier ().
I'm going to post my updates in here, but does anyone else want to try it as well? It only takes about 15 mins of your day 3 times a week