This has just gone around at work, and might be useful information to people here.
If you have a photocard driving license, check carefully section 4b. This is the date of expiry of the card - 10 years from when you were first issued a card with that photograph. You must update the photograph and pay £17.50 to get a new card.
The 10 years is NOT reset if you move house and get a new card with your new address - it's all about the photograph. The first cards were issued in 1998, and so have now expired. It's a good thing I found out about this as mine expires in november.
The DVLA should send you a letter informing you of what to do, but most people don't realise this process is necessary. If you do not update it, you could be fined £1000.