Only commuted once since the clocks changed so far, but not noticed cars any closer when overtaking ... but I have heard them maintain speed until fairly close behind and it sounds like they brake heavily ...and floor it to overtake. Odd given that I have three lights and loads of reflectors on the back including a Smart 1Watt, Cateye TDL1100 and a Moon one. I guess it's that they can see the lights but find it hard to judge how far away you are.
I did encounter one IDIOT though. I was going round a long sweeping bend that's maybe about 1/3rd mile long. The car behind me appeared to be patient and was waiting ... until about half way round the bend and they decided to overtake. Okay, with it being dark they could imply nothing was coming - unless it was a ninja cyclist with dim/no lights. But what really shocked me was that the car immediately behind them also overtook, and proceeded to overtake the car that overtook me ... still going round this blind(ish) bend. If there was a cyclist on that side of the road they probably would have been toast.
Sadly I didn't get the full licence plate or the make of car.