What's forced logging?
You mean forced logout? Well, both are optionally, actually. You can enable or disable the log globally - or turn on/off specific events. Forced logout is optional also, you can set cookies for 2 years and I doubt someone will stay on your forum non-stop for 2 years! That's the default UBB setting. Or, you can set session only, which means they stay on as long as their browser is open and on your forum.
The one thing I make sure of is... all settings are options.

BTW, folks, I just added in a Javascript Alert dialog when users get timed out and kicked out. It's a wordlet, of course so you can customize!