The teen wizard has outrun Slumdog Millionaire to claim the title of 2009's biggest box-office hit, although a bunch of guinea pigs could steal his fire this weekendThe 2009 heavyweightAfter just 12 days on release, Harry Potter and the Half-Blood Prince has amassed £33.07m to trump Slumdog Millionaire (£31.66m) as 2009's biggest box-office hit.