In UK registrations the 3rd and 4th digit signifies year since 2001.
In the first half of the year, the registration is the last 2 digits of the year.
In the second half of the year, it's made by the last 2 digits of the year + 50.
I.e. my old car was WX51 PVL. This made it a "51" plate, which meant it was from the later half of 2002. Same for my bike, KE51 OHL.
My current car is CV04 ***. This means it's from the first half of 2004.
The "60" plate has just come out. You can see this on the front of the VW van - PN60 ZVZ.
Generally cars are valued age wise by the reg, thus why people wait for a new reg to come out before they buy their cars (otherwise when they come to sell their car will look 6 months older).
The first 2 digits also show which DVLA office the car was registered in. Mine is "CV" which from memory is Cheltenham.
The last 3 digits are random.