Restore windows and scrollback after relaunch
By marcus.boin... on August 01, 2011 07:52 (imported from Google Code)
I requested this a long time ago for iTerm 1, and Terminal.app now does this in Lion.
Obviously you can't restore everything about the context of a terminal session, but restoring the scrollback buffer and the connection is a good start, and will at least help you restore a session manually to the point you were at before.