Check out the HUD in the second picture. It reads 77 kmh but the needle is reading about 68khm. I wish they'd use actual pictures. These poor Photoshops don't do any justice.
"They can project the temporary speed limit or other hazard information onto the HUD, as shown here."
From my experience BMW's HUD is the greatest feature of all. Very useful. The speedometer helps drastically, you don't need to shift eyes from the road. Much safer driving.