The fun look is much in evidence as the city turns back the clock from austerity to fun times, with punters pouring into the pubs and clubs.
The jumpers -- often featuring Christmas lights -- are a favourite with those on 12 Pubs Of Christmas outings.
This year one company has even come up with 'the jumper dress' for the fairer sex.
The Christmas jumper trend is now going global -- last night singer Cheryl Cole posted an image of herself in her own illuminated Christmas jumper.
With or without the zany jumpers, revellers are set to make this weekend the busiest of the year for the hard-pressed hospitality industry.
Pubs, clubs and restaurants are bracing themselves for a hectic few nights after a pretty grim year.
They have been reporting "very strong" business in Dublin city centre. "There's always a burst at this time of year, but 2012 has been especially strong," said Brendan Duignan, manager of the Old Stand, Exchequer St in Dublin city centre.
"Last weekend was extremely good and the weekend before was extremely good."
Kenny Whelan, of the nearby International Bar, also reported brisk business with many pub-goers starting the socialising earlier than usual in the day.
"We've noticed that it's gotten busy a bit earlier in the day rather than just night-time trade only," he said.
Ian Tucker, owner of the Exchequer was also enthusiastic. "Certainly this year has been very good in comparison to last year," he said.
The taxi trade has also been enjoying a Christmas boom. Drivers reported that business was strong, particularly last weekend.