It is becoming increasingly common for people to celebrate it, however not to the same degree as in the USA. Adults may throw the odd party depending on what day of the week the 31st falls, and children will trick or treat, but generally not in huge numbers. Too many houses don't provide candy for it to be worth the night out, and I personally am usually tempted to say trick just to see the look of confusion on the children's faces when they have to think up a trick on the spot. I say I am tempted because I don't want there to be the one kid who has got an egg and thinks it counts as a trick. SO in short: Yes halloween is celebrated, but not to the same degree as in the USA.