It's only in UK GAME stores y'see.

From April 5th a GAME store near you may be having a little MArio Kart Wii event, letting you play the new game, and if you're a good enough racer, perhaps even win prizes, including copies of the game itself!

The following stores are participating:

MANCHESTER: Unit 59, Arndale Centre
TRAFFORD: 124 Peel Centre, Trafford Centre
BOURNEMOUTH: Unit 4, Avenue Centre, Commercial Road
PORSTMOUTH: 226 Commercial Road
STEVENAGE: Unit 4A, The Forum
MERRYHILL: Unit 87, Lower Mall, Merryhill Shopping Centre
READING: Unit 18, Oracle Shopping Centre
BASINGSTOKE: Unit 15, Festival Place
BRAEHEAD: Unit 57, Braehead Shopping Centre, Kings Inch Rd
GLASGOW: 146 Sauchiehall Street
MILTON KEYNES: 15 Crown Walk
NOTTINGHAM: Unit 308A, Victoria Centre
LEEDS: 50-52 Albion Street
LUTON: 142-144 Arndale Centre
CHELTENHAM: Unit A, 100/104 High Street
CRIBBS CAUSEWAY: Unit LR53, Cribbs Causeway
CARDIFF: 92 Queen Street
NEWCASTLE: Fenwicks, 39 Northumberland Street
GATESHEAD METRO CENTRE: 17 Red Pathway
BLACKBURN: 10-12 Market Way
WIGAN: 27 Standish Gate
HANLEY: 214-215 The Potteries
LONDON: Hamleys, 188-196 Regent Street
LONDON:100 Oxford Street
THURROCK: Unit 106, Lakeside Shopping Centre
ROMFORD: Unit 15, Liberty 2 Centre
TAUNTON: 45-46 Fore Street
EDINBURGH: 127 Princes Street
DUNDEE: 51 Murraygate
KINGSTON-UPON-THAMES: 3rd Floor, The Bentalls Center

For me at least, this is depressing, because none of the stores seem to be anywhere near me... And I know of 3 stores which would be good locations...

Ah well, I hope some of you lot go and tell me how awesome it all is...

Source.