Camelot recently (October IIRC) re-jigged the National Lottery game rules.

They decided that they make more money when there are roll-overs so they've made it harder to win the big jackpot so there will be more roll-overs. Where as before you had to pick 6 numbers from 49, now you have to pick 6 from 59.
Adding the 10 extra balls has meant that the odds of winning the big prize has gone from ~1 in 14 million to ~1 in 45 million (similar odds to winning the Euromillions lottery jackpot).

In compensation they've included a millionaire raffle in each draw so someone is guaranteed to win a million pounds in each draw (the raffle used to net you £20k with the occasional 'special' million pound one). There is also now a 'prize' for successfully getting 2 numbers - you get a lucky dip ticket for the next draw. Otherwise the prize tiers are the same as they were from when they increased the ticket price to £2 - 3 balls nets you £25 and more gets you more (usually).

Thanks for the explanation. Sounds like they're scamming the public though.

It's a lottery, what did you expect? As with any form of gambling, you shouldn't play if you can't afford to lose the money.

Ooh, free gambling advice too!