Volkswagen offer a simple one off £250 service plan that covers you for 36months/30000 miles.
Cars must be set onto Time/Distance (annual) servicing and will qualify you for:
at 12mths/10000 miles - Oil Change service
at 24mths/20000 miles - Interval service (including oil change)
at 36mths/30000 miles - Inspection service (inc oil and brake fluid change)
This is available for all Golfs delivered before the end of the year (although the almost certainly will extend it)
herbie: It sounds like your dealer is offering you their own internal version which is normally for used cars as you won't need an MOT for three years (as simonpolly said).
There should be posters in your dealership advertising this offer. If not, you may want to point them towards this:
http://www.volkswagen.co.uk/#/new/golf-gti-vi/buying-guide/offers/You can buy these plans upto 30days after your car was registered or it can be added onto a finance agreement! We have about an 80% uptake on these....
Hope that helps