Father Christmas says "blooming" 75 times.
The towel Father Christmas uses after his bath has the initials NP on it, suggesting that he stole it from Nero's Palace, where he stayed in Las Vegas.
When Father Christmas goes to the pub in Scotland, Jim and Hilda from When the Wind Blows (1986) (also a Raymond Briggs' graphic novel/animated film) can be seen amongst the pub-goers.
The first half of the special is actually based on the second of Raymond Briggs' 'Father Christmas' books, 'Father Christmas Goes on Holiday' published in 1975. The second half is based on the original 'Father Christmas' book, published in 1973.