V1.8alpha prevents auto recognizing displayport changes
 

I tried out the 1.8 alpha and except for the wrong timing/resolution(?) that has already been reported (the display is not fully covered by the screen on my Samsung SyncMaster 2333) I also found that with the 1.8a driver installed any changes on the displayport (inserting or removing a monitor) was not automatically recognized.

Inserting a display was not a big problem because you can manually search for displays and that did the trick.

Removing a display was more problematic since the main screen was still on the disconnected display. So only resolution was to reboot every time I moved from my workplace.

So I have reverted back to 1.7 which seems to be working perfectly in this respect.

MacBook Pro 13" i7, early 2011
Lion 10.7.3 Swedish