Not that it has any effect on the rankings. But I'm pleasantly surprised to see some clients sites going up. It seems that over the last couple of years, large well established sites have been on a downward trend dropping from PR4s or 5s down to 3's.
I've never indulged in
PR sculpting using no-follows etc and have always supported drip-feeding as much quality copy on to sites as possible so perhaps I've just been diluting the
PR over time.