Hi Bryan,
That page is an old blog post from June 2005 and if you'll notice, the url in the post for forums doesn't work anymore. At thetime, mojoPortal.com was hosted on Linux/Mono and the url worked, but when 2.0 .NET came out I had to move to Windows hosting because it would take Mono a while to catchup.
If .NET is truly handling all requests, the extensionless urls will work as it does work on mono, but if IIS is handling the url first then it will interpret the lasdt segment of the url as a folder and will look for that folder and try to find a default document like Default.aspx or index.html (depending on configuration of course)
So in IIS if I want to use the friendly url
http://mysite.com/forums
if .NET was the first in the chain to handle this request, then my friendly url would be ~/forums and it would map to ~/Default.aspx?pageid=x and no .aspx extension would be needed in the friendly url.
In a normal IIS environment, it will result in 404 page not found, but if I actually create a folder named forums and put an empty Default.aspx file there to be a default document, then IIS will hand the request to .NET
Now in order to make .NET handle the request correctly, I need a friendly url mapping with the friendly url
~/forums/Default.aspx mapping to ~/Default.aspx?pageid=x
In my opinion its really too much trouble trying to use extensionless urls on Windows and my recommendation is just use .aspx extensions to keep it simple.
I really don't know much about the wildcard application map or what it is for or how to use it, so I don't know the answer to that question. My emphasis is on making mojoportal work in common hosted environments rather than making sure it supports all manner of custom environments.
I will add a config option about the forcing of lower case for suggested friendly urls in the next release, it is currently not configurable. Myself I think its best to use lower case for several reasons though I will make it an option for those who disagree. In trying to be a truly cross platform solution I always want to use consistent and correct casing for urls because only Windows has case insensitive file system and on *nix systems /Forums.aspx is not the same url as /forums.aspx and would result in a 404 if the real url is forums.aspx. So to insure it will work if I ever decide to move the site again to linux/Mono hosting I want to make sure my urls are consistent and lower case urls are easier to type and since they are case sensitive on other platforms I don't want users to have to type the url in correct mixed casing to avoid 404, instead I expect them to always use lower case.
Best,
Joe