There's a new membership-based discussion forum that's been active for about
a month now. It's at http://www.cessna-pilots.com

Membershp is free, although most of the users expect some type of fee in a
year or so. There are close to 500 members registered at this point.

You don't have to own a Cessna, but you'll probably get better mileage from
reading the posts if you do.

There are separate discussion forums for each type of Cessna (172, 182,
300-series, etc.), general maintenance, piloting, etc.

I have no principal stake in this website - I am just a plain 'ol member who
enjoys increasing my type-specific knowledge.

Carl