* mIRC now has a 'check for timed out connections' option in connect/options dialog. When this is set mIRC pings the server every so often if it hasn't heard form the server for a while to test your connection.
* Support for initiating passive dcc send/chat connections has been added.
* Changing the default font for a window type now affects all open windows of the same type immediately.
* Most file dialogs are now resizable.
* You can disable the $decode identifier (and various other "dangerous" commands) in the Lock options dialog. (The $decode is of course disabled by default.)
* Lots of SSL things have improved and mIRC now also supports SSL connections for sockets