I dislike the free-form overlapping windows, but tiling is still worse. Tiling could be better if windows had a 'reduced' mode: which needs minimal screen area to show status. Some examples: I like the last two lines of IM and terminal windows to show. I like to see the folder status on Thunderbird peeking out from behind other windows. I only need the smallest portion of the top left title bar to show for plain documents (they have no 'status').
Three screens help. :)