It's still there.
The last three cars I bought all came with the comment from the salesman "it's OK just drive it"
Looking at the handbook however there is always a reference to not exceeding certain (eg 3000) revs in the first 1500kms. The gearing on modern cars can frequently mean that on top gear the rev limit during "running in" is higher than the gearing required to do 70mph.
The books also say do not use full acceleration, brake hard or corner quickly as the brake pads, discs and tyres bed in.