I tried searching around to see if it was suggested before but did find anything. I think it will be very useful to add the thread start date on the forums thread list right next to the thread starter name. This is especially useful in the Buy, Sell or Trade forums when you don’t want to go over offers you already looked at before, but I can see myself using this in other places as well.
It already shows as thread is "2 Days old" or 10 days old......... The indirect way to what u said, but is related one.