A few thoughts
I saw this for the first time today on UK tv and a few things really struck me. Firstly i thought the special effects were superb (especially for the time). Compare the effects for a more modern film like Disney's 'Honey I shrunk the kids' made 30 years later against this. The effects in this 1959 film are vastly superior compared to the later one, and much much more convincing.
Secondly i was very surprised to see from this site that Janet Munro died so ridiculously young. What a terrible shame. I suppose i shouldn't have been that surprised to find out she was actually English as i noticed several fake Irish accents throughout the movie (the director was also English). I see from Wikipedia that the bulk of the film was actually made in California (with just a few additional wide shots of the countryside filmed in Ireland)) and that there was a mild controversy when it was first shown in Dublin because of the stereotyping within. I admit the depictions are very twee at times and the way the people are presented as simple, heavy drinking, dancing, singing and very superstitious may be viewed with a certain amount of disdain. However I would be curious to know if any Irish still take any offence to these flaws.