I agree with you. I'd love to see some data for this, but I have to think that the vast majority of records set over recent history are on the hot side...it just does not get as consistently cold as it used to during the winter. Outside of one winter several years back, snowfall is almost impossible to keep on the ground for more than a few days.
Where i really see the difference though is night time lows. Our lows temps year round seem way warmer than they were years ago.