Ranked in these QuestionsQuestion Ranking
Pro Supports shared sessions
More than one user can be connected to a single screen session.
Pro Also works as serial port terminal
This is actually very valuable for embedded or networking work.
Pro Preserve your session
Screen allows multiple terminals (screens) within a single screen number, so when you reconnect they will all be there.
Con Scrolling becomes tricky
You can no longer scroll with your mouse wheel, unless you do Ctra-a + Escape first
Con Doesn't work too well with ssh X connections
If you have an X connection over ssh within screen, it likely won't reconnect when you reconnect your screen.